添加项目文件。

ModbusDemo.sln

+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio 15
+VisualStudioVersion = 15.0.27703.2042
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ModbusDemo", "ModbusDemo\ModbusDemo.csproj", "{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {A1C8BC4E-F325-41B4-8D8A-6DD96C556151}
+	EndGlobalSection
+EndGlobal

ModbusDemo/414P.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ModbusDemo
+{
+    class _414P
+    {
+        //铂电阻+2路开关
+        const int MAX_AN_CH_NUM = 4;
+        ushort[] typeData = new ushort[MAX_AN_CH_NUM];//当前量程读数
+        byte[] AbnoSignal = new byte[MAX_AN_CH_NUM];//通道异常信号
+        ushort[] Inputtype = new ushort[MAX_AN_CH_NUM];//输入类型
+        ushort[] m_u16ADData = new ushort[MAX_AN_CH_NUM];  //保存AD的值
+        string[] WireN=new string[] { "2-Wire","3-Wire" ,"4-Wire"};
+        string[] Strcom = new string[] {"PT100(385) -50~150℃","PT100(385) 0~100℃",
+                                        "PT100(385) 0~200℃","PT100(385) 0~400℃",
+                                        "PT100(385) -200~200℃","PT100(391) -50~150℃",
+                                        "PT100(391) 0~100℃","PT100(391) 0~200℃",
+                                        "PT100(391) 0~400℃","PT100(391) -200~200℃",
+                                        "PT1000 -40~160℃","BALCO 500 -30~120℃",
+                                        "Ni(50) -80~100℃","Ni(508) 0~100℃"};
+        public class UserInfo
+        {
+            public int UserId { get; set; }
+            public string UserCompany { get; set; }
+
+            public float Data { get; set; }
+
+            public ushort UserModel { get; set; }
+            public double[] NegMin = {-50, 0, 0, 0, -200.00, -50.00,
+                                      0, 0, 0, -200.00, -40, -30, -80, 0 }; //负数最小值
+
+            public double[] NegMax = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};//负数最大值
+
+            public double[] PosMin = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+            //正数最小值
+            public double[] PosMax = { 150, 100, 200, 400, 200, 150, 100, 200,
+                                       400, 200, 160, 120 ,100, 100};
+            //正数最大值
+
+            public ushort[] usMin = {0xD556, 0x0000, 0x0000, 0x0000, 0x8000, 0xD556, 0x0000 ,
+                                 0x0000, 0x0000, 0x8000, 0xE000, 0xE000, 0x999A, 0x0000};
+
+            public ushort[] usMax = {0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF,0x7FFF, 0x7FFF,
+                                 0x7FFF ,0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF, 0x7FFF};
+        }
+        UserInfo passageway0 =new UserInfo();
+        UserInfo passageway1 = new UserInfo();
+        UserInfo passageway2 = new UserInfo();
+        UserInfo passageway3 = new UserInfo();
+        public string[] RtdValue(ushort[] typeData, ushort[] Inputtype)
+        {
+            string[] Valuepass = new string[MAX_AN_CH_NUM];
+            if (typeData != null || Inputtype != null)
+            {
+                passageway0.UserId = 0;//通道
+                passageway0.Data = typeData[0];//数据
+                passageway0.UserCompany = Strcom[Inputtype[0]];//通道类型
+                passageway0.UserModel = Inputtype[0];//确定计算公式
+
+                passageway1.UserId = 1;//通道
+                passageway1.Data = typeData[1];//数据
+                passageway1.UserCompany = Strcom[Inputtype[1]];//通道类型
+                passageway1.UserModel = Inputtype[1];//确定计算公式
+
+                passageway2.UserId = 2;//通道
+                passageway2.Data = typeData[2];//数据
+                passageway2.UserCompany = Strcom[Inputtype[2]];//通道类型
+                passageway2.UserModel = Inputtype[2];//确定计算公式
+
+                passageway3.UserId = 3;//通道
+                passageway3.Data = typeData[3];//数据
+                passageway3.UserCompany = Strcom[Inputtype[3]];//通道类型
+                passageway3.UserModel = Inputtype[3];//确定计算公式
+
+                //////输入格式为：NegMin   NegMax  PosMin  PosMax usMin usMax
+                Valuepass[0] = current(passageway0.NegMin[passageway0.UserModel], passageway0.NegMax[passageway0.UserModel], passageway0.PosMin[passageway0.UserModel],
+                    passageway0.PosMax[passageway0.UserModel], passageway0.usMin[passageway0.UserModel], passageway0.usMax[passageway0.UserModel],
+                    passageway0.Data); //处理函数
+
+                Valuepass[1] = current(passageway1.NegMin[passageway1.UserModel], passageway1.NegMax[passageway1.UserModel], passageway1.PosMin[passageway1.UserModel],
+                                passageway1.PosMax[passageway1.UserModel], passageway1.usMin[passageway1.UserModel], passageway1.usMax[passageway1.UserModel],
+                                passageway1.Data); //处理函数
+
+                Valuepass[2] = current(passageway2.NegMin[passageway2.UserModel], passageway2.NegMax[passageway2.UserModel], passageway2.PosMin[passageway2.UserModel],
+                    passageway2.PosMax[passageway2.UserModel], passageway2.usMin[passageway2.UserModel], passageway2.usMax[passageway2.UserModel],
+                    passageway2.Data); //处理函数
+
+                Valuepass[3] = current(passageway3.NegMin[passageway3.UserModel], passageway3.NegMax[passageway3.UserModel], passageway3.PosMin[passageway3.UserModel],
+                    passageway3.PosMax[passageway3.UserModel], passageway3.usMin[passageway3.UserModel], passageway3.usMax[passageway3.UserModel],
+                    passageway3.Data); //处理函数
+                return Valuepass;
+            }
+            else
+            return Valuepass=null;
+        }
+
+        double parameter;
+        string parameter2;
+        //输入格式为：NegMin   NegMax  PosMin  PosMax usMin usMax
+        public string current(double NegMin, double NegMax, double PosMin,
+            double PosMax, double usMin, double usMax,
+            float Input) //处理函数
+        {
+            if (Input >= 0x0000
+             && Input <= 0x7FFF)
+            {
+                parameter = Convert.ToSingle(PosMin + ((PosMax - PosMin) * Input) / usMax);
+                parameter2 = parameter.ToString("F3");
+
+            }
+            else
+            {
+                parameter = -Convert.ToSingle(PosMin + ((PosMax - PosMin) * (0x10000 - Input)) / (0x10000 - usMax));
+                parameter2 = parameter.ToString("F3");
+            }
+
+            if (parameter2 == "0.000")
+            {
+                parameter2 = "0.0";
+                return parameter2;
+            }
+            else
+                return parameter2;
+        }
+
+
+
+
+
+
+    }
+}

ModbusDemo/478C.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ModbusDemo
+{
+    class _478C
+    {
+       
+        public int [] IO(bool [] state)
+        {
+            int[] I = new int[state.Length];
+            for (int i = 0; i < state.Length; i++)
+            {
+                I[i] = Convert.ToInt32(state[i]);
+            }
+            return I;
+        }
+    }
+}

ModbusDemo/ComPort.Designer.cs

+namespace ModbusDemo
+{
+    partial class ComPort
+    {
+        /// <summary> 
+        /// 必需的设计器变量。
+        /// </summary>
+        private System.ComponentModel.IContainer components = null;
+
+        /// <summary> 
+        /// 清理所有正在使用的资源。
+        /// </summary>
+        /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
+        protected override void Dispose(bool disposing)
+        {
+            if (disposing && (components != null))
+            {
+                components.Dispose();
+            }
+            base.Dispose(disposing);
+        }
+
+        #region 组件设计器生成的代码
+
+        /// <summary> 
+        /// 设计器支持所需的方法 - 不要修改
+        /// 使用代码编辑器修改此方法的内容。
+        /// </summary>
+        private void InitializeComponent()
+        {
+            this.label7 = new System.Windows.Forms.Label();
+            this.labPort = new System.Windows.Forms.Label();
+            this.cmbPort = new System.Windows.Forms.ComboBox();
+            this.cmbStopBit = new System.Windows.Forms.ComboBox();
+            this.btCloseCOM = new System.Windows.Forms.Button();
+            this.cmbParity = new System.Windows.Forms.ComboBox();
+            this.btOpenCOM = new System.Windows.Forms.Button();
+            this.cmbDataBit = new System.Windows.Forms.ComboBox();
+            this.labStopBit = new System.Windows.Forms.Label();
+            this.labParity = new System.Windows.Forms.Label();
+            this.labBaud = new System.Windows.Forms.Label();
+            this.labDataBit = new System.Windows.Forms.Label();
+            this.cmbBaud = new System.Windows.Forms.ComboBox();
+            this.SuspendLayout();
+            // 
+            // label7
+            // 
+            this.label7.Font = new System.Drawing.Font("Arial", 8F);
+            this.label7.ForeColor = System.Drawing.Color.Blue;
+            this.label7.Location = new System.Drawing.Point(3, 17);
+            this.label7.Name = "label7";
+            this.label7.Size = new System.Drawing.Size(140, 17);
+            this.label7.TabIndex = 47;
+            this.label7.Text = "Connection Status";
+            // 
+            // labPort
+            // 
+            this.labPort.Font = new System.Drawing.Font("Arial", 8F);
+            this.labPort.Location = new System.Drawing.Point(3, 34);
+            this.labPort.Name = "labPort";
+            this.labPort.Size = new System.Drawing.Size(75, 15);
+            this.labPort.TabIndex = 53;
+            this.labPort.Text = "COM Port";
+            this.labPort.TextAlign = System.Drawing.ContentAlignment.TopCenter;
+            // 
+            // cmbPort
+            // 
+            this.cmbPort.Font = new System.Drawing.Font("Arial", 8F);
+            this.cmbPort.Location = new System.Drawing.Point(3, 49);
+            this.cmbPort.Name = "cmbPort";
+            this.cmbPort.Size = new System.Drawing.Size(75, 22);
+            this.cmbPort.TabIndex = 52;
+            // 
+            // cmbStopBit
+            // 
+            this.cmbStopBit.Font = new System.Drawing.Font("Arial", 8F);
+            this.cmbStopBit.Items.AddRange(new object[] {
+            "1",
+            "2"});
+            this.cmbStopBit.Location = new System.Drawing.Point(337, 49);
+            this.cmbStopBit.Name = "cmbStopBit";
+            this.cmbStopBit.Size = new System.Drawing.Size(56, 22);
+            this.cmbStopBit.TabIndex = 57;
+            // 
+            // btCloseCOM
+            // 
+            this.btCloseCOM.Enabled = false;
+            this.btCloseCOM.Font = new System.Drawing.Font("Arial", 8F);
+            this.btCloseCOM.Location = new System.Drawing.Point(315, 75);
+            this.btCloseCOM.Name = "btCloseCOM";
+            this.btCloseCOM.Size = new System.Drawing.Size(78, 23);
+            this.btCloseCOM.TabIndex = 59;
+            this.btCloseCOM.Text = "Close";
+            this.btCloseCOM.Click += new System.EventHandler(this.btCloseCOM_Click);
+            // 
+            // cmbParity
+            // 
+            this.cmbParity.Font = new System.Drawing.Font("Arial", 8F);
+            this.cmbParity.Items.AddRange(new object[] {
+            "0-None Parity",
+            "1-Odd Parity",
+            "2-Even Parity"});
+            this.cmbParity.Location = new System.Drawing.Point(224, 49);
+            this.cmbParity.Name = "cmbParity";
+            this.cmbParity.Size = new System.Drawing.Size(100, 22);
+            this.cmbParity.TabIndex = 56;
+            // 
+            // btOpenCOM
+            // 
+            this.btOpenCOM.Font = new System.Drawing.Font("Arial", 8F);
+            this.btOpenCOM.Location = new System.Drawing.Point(224, 75);
+            this.btOpenCOM.Name = "btOpenCOM";
+            this.btOpenCOM.Size = new System.Drawing.Size(78, 23);
+            this.btOpenCOM.TabIndex = 58;
+            this.btOpenCOM.Text = "Open";
+            this.btOpenCOM.Click += new System.EventHandler(this.btOpenCOM_Click);
+            // 
+            // cmbDataBit
+            // 
+            this.cmbDataBit.Font = new System.Drawing.Font("Arial", 8F);
+            this.cmbDataBit.Items.AddRange(new object[] {
+            "7",
+            "8"});
+            this.cmbDataBit.Location = new System.Drawing.Point(168, 49);
+            this.cmbDataBit.Name = "cmbDataBit";
+            this.cmbDataBit.Size = new System.Drawing.Size(48, 22);
+            this.cmbDataBit.TabIndex = 55;
+            // 
+            // labStopBit
+            // 
+            this.labStopBit.Font = new System.Drawing.Font("Arial", 8F);
+            this.labStopBit.Location = new System.Drawing.Point(337, 34);
+            this.labStopBit.Name = "labStopBit";
+            this.labStopBit.Size = new System.Drawing.Size(56, 15);
+            this.labStopBit.TabIndex = 60;
+            this.labStopBit.Text = "Stop Bit";
+            this.labStopBit.TextAlign = System.Drawing.ContentAlignment.TopCenter;
+            // 
+            // labParity
+            // 
+            this.labParity.Font = new System.Drawing.Font("Arial", 8F);
+            this.labParity.Location = new System.Drawing.Point(226, 34);
+            this.labParity.Name = "labParity";
+            this.labParity.Size = new System.Drawing.Size(98, 15);
+            this.labParity.TabIndex = 61;
+            this.labParity.Text = "Parity";
+            this.labParity.TextAlign = System.Drawing.ContentAlignment.TopCenter;
+            // 
+            // labBaud
+            // 
+            this.labBaud.Font = new System.Drawing.Font("Arial", 8F);
+            this.labBaud.Location = new System.Drawing.Point(84, 34);
+            this.labBaud.Name = "labBaud";
+            this.labBaud.Size = new System.Drawing.Size(75, 15);
+            this.labBaud.TabIndex = 62;
+            this.labBaud.Text = "Baudrate";
+            this.labBaud.TextAlign = System.Drawing.ContentAlignment.TopCenter;
+            // 
+            // labDataBit
+            // 
+            this.labDataBit.Font = new System.Drawing.Font("Arial", 8F);
+            this.labDataBit.Location = new System.Drawing.Point(168, 34);
+            this.labDataBit.Name = "labDataBit";
+            this.labDataBit.Size = new System.Drawing.Size(48, 15);
+            this.labDataBit.TabIndex = 63;
+            this.labDataBit.Text = "Data Bit";
+            this.labDataBit.TextAlign = System.Drawing.ContentAlignment.TopCenter;
+            // 
+            // cmbBaud
+            // 
+            this.cmbBaud.Font = new System.Drawing.Font("Arial", 8F);
+            this.cmbBaud.Items.AddRange(new object[] {
+            "1200",
+            "2400",
+            "4800",
+            "9600",
+            "19200",
+            "38400",
+            "57600",
+            "115200"});
+            this.cmbBaud.Location = new System.Drawing.Point(83, 49);
+            this.cmbBaud.Name = "cmbBaud";
+            this.cmbBaud.Size = new System.Drawing.Size(76, 22);
+            this.cmbBaud.TabIndex = 54;
+            // 
+            // ComPort
+            // 
+            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
+            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
+            this.Controls.Add(this.cmbStopBit);
+            this.Controls.Add(this.btCloseCOM);
+            this.Controls.Add(this.cmbParity);
+            this.Controls.Add(this.btOpenCOM);
+            this.Controls.Add(this.cmbDataBit);
+            this.Controls.Add(this.labStopBit);
+            this.Controls.Add(this.labParity);
+            this.Controls.Add(this.labBaud);
+            this.Controls.Add(this.labDataBit);
+            this.Controls.Add(this.cmbBaud);
+            this.Controls.Add(this.labPort);
+            this.Controls.Add(this.cmbPort);
+            this.Controls.Add(this.label7);
+            this.Name = "ComPort";
+            this.Size = new System.Drawing.Size(400, 106);
+            this.Load += new System.EventHandler(this.ComPort_Load);
+            this.ResumeLayout(false);
+
+        }
+
+        #endregion
+
+        private System.Windows.Forms.Label label7;
+        private System.Windows.Forms.Label labPort;
+        private System.Windows.Forms.ComboBox cmbPort;
+        private System.Windows.Forms.ComboBox cmbStopBit;
+        private System.Windows.Forms.Button btCloseCOM;
+        private System.Windows.Forms.ComboBox cmbParity;
+        private System.Windows.Forms.Button btOpenCOM;
+        private System.Windows.Forms.ComboBox cmbDataBit;
+        private System.Windows.Forms.Label labStopBit;
+        private System.Windows.Forms.Label labParity;
+        private System.Windows.Forms.Label labBaud;
+        private System.Windows.Forms.Label labDataBit;
+        private System.Windows.Forms.ComboBox cmbBaud;
+    }
+}

ModbusDemo/ComPort.cs

+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Drawing;
+using System.Data;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Forms;
+using System.IO.Ports;
+
+namespace ModbusDemo
+{
+    public partial class ComPort : UserControl
+    {
+        public ComPort()
+        {
+            InitializeComponent();
+            System.Windows.Forms.Control.CheckForIllegalCrossThreadCalls = false;//设置该属性 为false
+        }
+        private byte slaveID = 1;
+        private SerialPort comPort = new SerialPort();
+
+        private void ComPort_Load(object sender, EventArgs e)
+        {
+            cmbBaud.SelectedIndex = 7;
+            cmbDataBit.SelectedIndex = 1;
+            cmbParity.SelectedIndex = 0;
+            cmbStopBit.SelectedIndex = 0;
+            foreach (string s in SerialPort.GetPortNames())
+                cmbPort.Items.Add(s);
+            cmbPort.SelectedIndex = -1;
+        }
+
+        private void btOpenCOM_Click(object sender, EventArgs e)
+        {
+            if (cmbPort.Text == "")
+            {
+                MessageBox.Show("串口打开错误");
+                return;
+            }
+            comPort.PortName = cmbPort.Text;
+            comPort.BaudRate = int.Parse(cmbBaud.Text);
+            comPort.DataBits = int.Parse(cmbDataBit.Text);
+            if (cmbParity.Text.Substring(0, 1) == "0")
+            {
+                comPort.Parity = Parity.None;
+            }
+            else if (cmbParity.Text.Substring(0, 1) == "1")
+            {
+                comPort.Parity = Parity.Odd;
+            }
+            else if (cmbParity.Text.Substring(0, 1) == "2")
+            {
+                comPort.Parity = Parity.Even;
+            }
+            if (cmbStopBit.Text == "0")
+            {
+                comPort.StopBits = StopBits.None;
+            }
+            else if (cmbStopBit.Text == "1")
+            {
+                comPort.StopBits = StopBits.One;
+            }
+            try
+            {
+                comPort.Open();
+               //comPort.Write("01 03 00 00 00 05 85 C9");//写数据
+                comPort.DataReceived += new SerialDataReceivedEventHandler(post_DataReceived);//串口接收处理函数
+                btOpenCOM.Enabled = false;
+                btCloseCOM.Enabled = true;
+                Console.WriteLine(DateTime.Now.ToString() + " =>Open " + comPort.PortName + " sucessfully!");
+                //MessageBox.Show(DateTime.Now.ToString() + System.Environment.NewLine + " =>Open " + comPort.PortName + " sucessfully!");
+            }
+            catch (Exception ex)
+            {
+                Console.WriteLine("Error: " + ex.Message);
+                MessageBox.Show("Error: " + ex.Message);
+                return;
+            }
+        }
+        //字节数组转16进制字符串
+        public static string byteToHexStr(byte[] bytes)
+        {
+            string returnStr = "";
+            if (bytes != null)
+            {
+                for (int i = 0; i < bytes.Length; i++)
+                {
+                    returnStr += bytes[i].ToString("X2");
+                }
+            }
+            return returnStr;
+        }
+        static int buffersize = 18;   //十六进制数的大小（假设为9Byte,可调整数字大小）
+        byte[] buffer = new Byte[buffersize];   //创建缓冲区
+
+        private void post_DataReceived(object sender, SerialDataReceivedEventArgs e)
+        {
+            int size = 0;
+            
+            comPort.Read(buffer, 0, buffersize);
+            string ss;
+            ss = byteToHexStr(buffer); //用到函数byteToHexStr
+
+            Console.WriteLine(comPort.ReadExisting());
+            Console.WriteLine(ss);
+
+            size = comPort.ReadBufferSize;
+
+            if (buffer[0]==255)
+            {
+                modbus_Master.TepArray[0] = buffer[0];
+                modbus_Master.Sign = 2;
+                Console.WriteLine(comPort.ReadExisting());
+            }
+            else 
+            {
+                modbus_Master.Sign =1;
+                modbus_Master.TepArray[0] = 0;
+            }
+        
+        }
+
+        private void btCloseCOM_Click(object sender, EventArgs e)
+        {
+                //Close comport first,then stop and dispose slave.
+                comPort.Close();
+                btOpenCOM.Enabled = true;
+                btCloseCOM.Enabled = false;
+                Console.WriteLine(DateTime.Now.ToString() + " =>Disconnect " + comPort.PortName);
+                MessageBox.Show(DateTime.Now.ToString() + System.Environment.NewLine + " =>Disconnect " + comPort.PortName);
+        }
+    }
+}

ModbusDemo/ComPort.resx

+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.objec
+    
+oap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+</root>
\ No newline at end of file

ModbusDemo/Common/ModSearch.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Net;
+using System.Net.Sockets;
+using System.Threading;
+using System.Text.RegularExpressions;
+using System.Collections;
+using System.Management;
+using System.Net.NetworkInformation;
+
+namespace ModbusDemo.windows
+{
+    class ModSearch
+    {
+        public struct DeviceInfo
+        {
+            public string ModuleName;
+            public string MacAddr;
+            public string IpAddr;
+            public string Netmask;
+            public string Gateway;
+            public bool bActive;
+        };
+
+        public UdpClient client;
+        public IPEndPoint endpoint;
+        Thread searchth;
+        ManualResetEvent mre = new ManualResetEvent(false);
+
+        public DeviceInfo m_DeviceInfo;
+        public ArrayList myHMIList = new ArrayList();
+
+        string FMAC =null;
+
+        string localip = null;
+
+        /// <summary>
+        /// 构造函数
+        /// </summary>
+        public ModSearch()
+        {
+            myHMIList.Clear();
+  
+            NetworkInterface[] nics = NetworkInterface.GetAllNetworkInterfaces();
+            foreach (NetworkInterface adapter in nics)
+            {
+                if (adapter.Name == "本地连接")  //这里是为了匹配我自己电脑网卡
+                {
+                    bool Pd1 = (adapter.NetworkInterfaceType == NetworkInterfaceType.Ethernet); //判断是否是以太网连接
+                    if (Pd1)
+                    {
+                        {
+                            IPInterfaceProperties ip = adapter.GetIPProperties();     //IP配置信息
+                            UnicastIPAddressInformationCollection ipCollection = ip.UnicastAddresses;
+                            foreach (UnicastIPAddressInformation ipadd in ipCollection)
+                            {
+                                if (ipadd.Address.AddressFamily == AddressFamily.InterNetwork)
+                                     this.localip = ipadd.Address.ToString();//获取ip
+                            }
+                        }
+                    }
+                }
+             }          
+        }
+
+        public void ThStart()
+        {
+            if (mre != null)
+                mre.Reset();
+            Console.WriteLine("搜索线程开始....");
+            searchth = new Thread(ThreadMethod);
+            searchth.IsBackground = true;
+            searchth.Start();         
+        }
+
+        public void ThStop()
+        {
+            Console.WriteLine("搜索线程结束....");
+            mre.Set();
+        }
+
+        public int HMICount()
+        {
+            return myHMIList.Count;
+        }
+
+        private void ThreadMethod()
+        {
+            byte[] sendBytes = new byte[] { 0x57, 0x54, 0x04, 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00, 0x55, 0xAA };
+            int iReadBytes = 0;
+
+            try
+            {
+               client = new UdpClient(new IPEndPoint(IPAddress.Any, 0));
+               // client = new UdpClient(new IPEndPoint(IPAddress.Parse(this.localip), 0));
+
+                endpoint = new IPEndPoint(IPAddress.Parse("255.255.255.255"), 5048);
+                client.Send(sendBytes, sendBytes.Length, endpoint);
+                Thread.Sleep(500);
+
+                byte[] recvBytes;
+                client.Client.Blocking = false;
+                while (!mre.WaitOne(500))
+                {
+                    iReadBytes = 30;
+                    int buffSizeCurrent;
+                    buffSizeCurrent = client.Client.Available;
+                    if (buffSizeCurrent > 0)
+                    {
+                        recvBytes = client.Receive(ref endpoint);
+                        iReadBytes = recvBytes.Length;
+                        DoRecvDataCallBack(recvBytes, iReadBytes);
+                    }
+                }
+            }catch
+            {
+               
+            }
+           
+        }
+
+        public Boolean DoRecvDataCallBack(byte[] pcData, int iRecvLength)
+        {
+            int i;
+            int count = 0;
+            byte[] pBuf = pcData;
+            int iDataLength = 0;
+         
+            if (iRecvLength < 8)
+                return false;
+
+            if ((pBuf[0] == (byte)0x57) && (pBuf[1] == (byte)0x54) && (pBuf[iRecvLength - 2] == (byte)0x55) && (pBuf[iRecvLength - 1] == (byte)0xAA))
+            {
+                iDataLength = (int)(pBuf[2] & 0xFF)
+                                | (int)((pBuf[3] & 0xFF) << 8)
+                                | (int)((pBuf[4] & 0xFF) << 16)
+                                | (int)((pBuf[5] & 0xFF) << 24);
+
+                if ((iDataLength >= 4) && (iRecvLength == 8 + iDataLength))
+                {                   
+                    System.Text.ASCIIEncoding asciiEncoding = new System.Text.ASCIIEncoding();
+                    m_DeviceInfo.bActive = false;
+                                      
+                    for (i = 0; i < 100; i++ )
+                    {
+                        if (asciiEncoding.GetString(pBuf, 6 + i, 1) == "\0")
+                            break;
+                        count++;
+                    }
+                   // m_DeviceInfo.ModuleName = String.Format("{0}", asciiEncoding.GetString(pBuf, 6, count));
+                    //脱机
+                    m_DeviceInfo.ModuleName = String.Format("{0}{1}{2}{3}", asciiEncoding.GetString(pBuf, 6, 1),
+                                                                                      asciiEncoding.GetString(pBuf, 7, 1),
+                                                                                        asciiEncoding.GetString(pBuf, 8, 1),
+                                                                                        asciiEncoding.GetString(pBuf, 9, 1));
+                    m_DeviceInfo.MacAddr = String.Format("{0}:{1}:{2}:{3}:{4}:{5}", pBuf[10], pBuf[11], pBuf[12], pBuf[13], pBuf[14], pBuf[15]);
+                    m_DeviceInfo.IpAddr = String.Format("{0}.{1}.{2}.{3}", pBuf[16], pBuf[17], pBuf[18], pBuf[19]);
+                    m_DeviceInfo.Netmask = String.Format("{0}.{1}.{2}.{3}", pBuf[20], pBuf[21], pBuf[22], pBuf[23]);
+                    m_DeviceInfo.Gateway = String.Format("{0}.{1}.{2}.{3}", pBuf[24], pBuf[25], pBuf[26], pBuf[27]);                  
+                    if (m_DeviceInfo.IpAddr != "0.0.0.0")
+                    {
+                        myHMIList.Add(m_DeviceInfo);
+                    }
+                   
+                    return true;
+                }
+            }
+            return false;
+        }
+    }
+}

ModbusDemo/Common/WTModbus.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Runtime.InteropServices;
+
+namespace ModbusDemo.windows
+{
+    class WTModbus
+    {
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnLibModbus", CharSet = CharSet.Unicode)]
+        public static extern uint fnLibModbus();
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadCoilStatus")]
+        public static extern int fnReadCoilStatus(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.Byte[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadInputStatus")]
+        public static extern int fnReadInputStatus(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.Char[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadHoldingReg")]
+        public static extern int fnReadHoldingReg(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.UInt16[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadInputReg")]
+        public static extern int fnReadInputReg(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.UInt16[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnWriteSingleCoil")]
+        public static extern int fnWriteSingleCoil(uint handle, ushort address, ushort state, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnWriteHoldingReg")]
+        public static extern int fnWriteHoldingReg(uint handle, ushort address, ushort state, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnWriteMultipleCoils")]
+        public static extern int fnWriteMultipleCoils(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.Char[] src, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnWriteMultipleRegs")]
+        public static extern int fnWriteMultipleRegs(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.UInt16[] src, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReportSlaveID")]
+        public static extern int fnReportSlaveID(uint handle, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.Char[] src, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnMaskWriteReg")]
+        public static extern int fnMaskWriteReg(uint handle, ushort address, ushort amask, ushort omask, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadWriteMultipleRegs")]
+        public static extern int fnReadWriteMultipleRegs(uint handle, ushort waddress, ushort wnum, ushort raddress, ushort rnum, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.UInt16[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnLibModbusClose")]
+        public static extern void fnLibModbusClose(uint handle);
+
+        private uint hModbusHandle;
+        private System.UInt16[] dest = new System.UInt16[10] { 0, 0, 3, 4, 5, 6, 7, 8, 9, 0 };
+
+        public WTModbus()
+        {
+            this.hModbusHandle = fnLibModbus();
+        }
+
+        ~WTModbus()
+        {
+            fnLibModbusClose(hModbusHandle);
+        }
+     
+        /// <summary>
+        /// 读线圈状态
+        /// </summary>
+        /// <param name="addr">地址</param>
+        /// <param name="num">线圈数目</param>
+        /// <param name="ip">设备IP</param>
+        /// <param name="wport">端口号 默认502</param>
+        /// <param name="buf">读取结果</param>
+        /// <returns>
+        /// 0 -- no error
+        /// 1 -- illegal register address.
+        /// 2 -- illegal argument
+        /// 3 -- porting layer error
+        /// 4 -- insufficient resources
+        /// 5 -- I/O error
+        /// 6 -- protocol stack in illegal state
+        /// 7 -- timeout error occurred
+        /// 8 -- slave address error
+        /// 9 -- exception error occurred
+        /// 10-- CRC check error
+        /// 11-- send data error
+        /// 12-- receive data error
+        /// 13-- TCP connect error
+        /// 14-- close error
+        /// </returns>
+        public int ReadCoilStatus(ushort addr, ushort num, String ip, ushort wport, ref byte[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadCoilStatus(hModbusHandle, (ushort)(addr - 1), num, buf, bIp, wport);     
+            return ret;
+        }
+
+        public int ReadInputStatus(ushort addr, ushort num, String ip, ushort wport, ref char[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadInputStatus(hModbusHandle, (ushort)(addr - 1), 1, buf, bIp, 502);
+            return ret;
+        }
+
+        public int ReadHoldingReg(ushort addr, ushort num, String ip, ushort wport, ref UInt16[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadHoldingReg(hModbusHandle, (ushort)(addr - 1), num, buf, bIp, wport);
+            return ret;
+        }
+
+        public int ReadInputReg(ushort addr, ushort num, String ip, ushort wport, ref UInt16[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadInputReg(hModbusHandle, (ushort)(addr - 1), 1, dest, bIp, wport);
+            buf[0] = dest[0];
+            return ret;
+        }
+
+        public int WriteSingleCoil(ushort addr, ushort state, String ip, ushort wport)
+        {
+            int ret = 0;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnWriteSingleCoil(hModbusHandle, (ushort)(addr - 1), state, bIp, wport);
+            return ret;
+        }
+
+        public int WriteHoldingReg(ushort addr, ushort state, String ip, ushort wport)
+        {
+            int ret = 0;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnWriteHoldingReg(hModbusHandle, (ushort)(addr - 1), state, bIp, wport);
+            return ret;
+        }
+
+        public int ReadHoldingReg(ushort addr, ushort num, String ip, ushort wport, ref char[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnWriteMultipleCoils(hModbusHandle, (ushort)(addr - 1), 1, buf, bIp, wport);
+            return ret;
+        }
+
+        public int WriteMultipleRegs(ushort addr, ushort num, String ip, ushort wport, ref ushort[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnWriteMultipleRegs(hModbusHandle, (ushort)(addr - 1), num, buf, bIp, wport);
+            return ret;
+        }
+
+        public int ReportSlaveID(ushort addr, ushort num, String ip, ushort wport, ref char[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReportSlaveID(hModbusHandle, buf, bIp, 502);
+            return ret;
+        }
+
+        public int MaskWriteReg(ushort addr, ushort amask, ushort omask, String ip, ushort wport)
+        {
+            int ret = 0;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnMaskWriteReg(hModbusHandle, (ushort)(addr - 1), amask, omask, bIp, wport);
+            return ret;
+        }
+
+        public int ReadWriteMultipleRegs(ushort waddr, ushort wnum, ushort raddr, ushort rnum, String ip, ushort wport, ref UInt16[] buf)
+        {
+            int ret = 0;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadWriteMultipleRegs(hModbusHandle, (ushort)(waddr - 1), wnum, raddr, rnum, buf, bIp, wnum);
+            return ret;
+        }
+    }
+}

ModbusDemo/Modbus-slave.resx

+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
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+  </metadata>
+</root>
\ No newline at end of file

ModbusDemo/ModbusDemo.csproj

+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="12.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}</ProjectGuid>
+    <OutputType>WinExe</OutputType>
+    <AppDesignerFolder>Properties</AppDesignerFolder>
+    <RootNamespace>ModbusDemo</RootNamespace>
+    <AssemblyName>WTG93UG</AssemblyName>
+    <TargetFrameworkVersion>v4.5.2</TargetFrameworkVersion>
+    <FileAlignment>512</FileAlignment>
+    <PublishUrl>publish\</PublishUrl>
+    <Install>true</Install>
+    <InstallFrom>Disk</InstallFrom>
+    <UpdateEnabled>false</UpdateEnabled>
+    <UpdateMode>Foreground</UpdateMode>
+    <UpdateInterval>7</UpdateInterval>
+    <UpdateIntervalUnits>Days</UpdateIntervalUnits>
+    <UpdatePeriodically>false</UpdatePeriodically>
+    <UpdateRequired>false</UpdateRequired>
+    <MapFileExtensions>true</MapFileExtensions>
+    <ApplicationRevision>0</ApplicationRevision>
+    <ApplicationVersion>1.0.0.%2a</ApplicationVersion>
+    <IsWebBootstrapper>false</IsWebBootstrapper>
+    <UseApplicationTrust>false</UseApplicationTrust>
+    <BootstrapperEnabled>true</BootstrapperEnabled>
+    <TargetFrameworkProfile />
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <PlatformTarget>x86</PlatformTarget>
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>bin\Debug\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <Prefer32Bit>false</Prefer32Bit>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <PlatformTarget>AnyCPU</PlatformTarget>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\Release\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <Prefer32Bit>false</Prefer32Bit>
+  </PropertyGroup>
+  <PropertyGroup>
+    <StartupObject>ModbusDemo.Program</StartupObject>
+  </PropertyGroup>
+  <PropertyGroup>
+    <ApplicationIcon>favicon.ico</ApplicationIcon>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="log4net">
+      <HintPath>Lib\log4net.dll</HintPath>
+    </Reference>
+    <Reference Include="MQTTnet, Version=0.0.0.0, Culture=neutral, processorArchitecture=MSIL">
+      <HintPath>..\packages\MQTTnet-CP.2.7.5\lib\net452\MQTTnet.dll</HintPath>
+      <EmbedInteropTypes>False</EmbedInteropTypes>
+    </Reference>
+    <Reference Include="Newtonsoft.Json, Version=12.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed, processorArchitecture=MSIL">
+      <HintPath>..\packages\Newtonsoft.Json.12.0.1\lib\net45\Newtonsoft.Json.dll</HintPath>
+    </Reference>
+    <Reference Include="nmodbuspc">
+      <HintPath>Lib\nmodbuspc.dll</HintPath>
+    </Reference>
+    <Reference Include="System" />
+    <Reference Include="System.Core" />
+    <Reference Include="System.Xml.Linq" />
+    <Reference Include="System.Data.DataSetExtensions" />
+    <Reference Include="Microsoft.CSharp" />
+    <Reference Include="System.Data" />
+    <Reference Include="System.Deployment" />
+    <Reference Include="System.Drawing" />
+    <Reference Include="System.Windows.Forms" />
+    <Reference Include="System.Xml" />
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="414P.cs" />
+    <Compile Include="478C.cs" />
+    <Compile Include="418X.cs" />
+    <Compile Include="Common\Modbuslib.cs" />
+    <Compile Include="ComPort.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="ComPort.Designer.cs">
+      <DependentUpon>ComPort.cs</DependentUpon>
+    </Compile>
+    <Compile Include="ConvertJson.cs" />
+    <Compile Include="windows\Form1.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="windows\Form1.Designer.cs">
+      <DependentUpon>Form1.cs</DependentUpon>
+    </Compile>
+    <Compile Include="modbus-Master.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="modbus-Master.Designer.cs">
+      <DependentUpon>modbus-Master.cs</DependentUpon>
+    </Compile>
+    <Compile Include="mqttpacke.cs" />
+    <Compile Include="RData.cs" />
+    <Compile Include="UData.cs" />
+    <Compile Include="windows\AC.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="windows\AC.Designer.cs">
+      <DependentUpon>AC.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Common\ModSearch.cs" />
+    <Compile Include="Common\WTModbus.cs" />
+    <Compile Include="windows\Demo_818X.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="windows\Demo_818X.Designer.cs">
+      <DependentUpon>Demo_818X.cs</DependentUpon>
+    </Compile>
+    <Compile Include="windows\frmInputValue.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="windows\frmInputValue.designer.cs">
+      <DependentUpon>frmInputValue.cs</DependentUpon>
+    </Compile>
+    <Compile Include="windows\MDemo.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="windows\MDemo.Designer.cs">
+      <DependentUpon>MDemo.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Modbus-slave.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="Modbus-slave.Designer.cs">
+      <DependentUpon>Modbus-slave.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Program.cs" />
+    <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="windows\ProTest.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="windows\ProTest.Designer.cs">
+      <DependentUpon>ProTest.cs</DependentUpon>
+    </Compile>
+    <Compile Include="UserMQTT.cs">
+      <SubType>UserControl</SubType>
+    </Compile>
+    <Compile Include="UserMQTT.Designer.cs">
+      <DependentUpon>UserMQTT.cs</DependentUpon>
+    </Compile>
+    <Compile Include="windows\sanchen.cs">
+      <SubType>Form</SubType>
+    </Compile>
+    <Compile Include="windows\sanchen.Designer.cs">
+      <DependentUpon>sanchen.cs</DependentUpon>
+    </Compile>
+    <Compile Include="Totxt.cs" />
+    <EmbeddedResource Include="ComPort.resx">
+      <DependentUpon>ComPort.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="windows\Form1.resx">
+      <DependentUpon>Form1.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="modbus-Master.resx">
+      <DependentUpon>modbus-Master.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="windows\AC.resx">
+      <DependentUpon>AC.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="windows\Demo_818X.resx">
+      <DependentUpon>Demo_818X.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="windows\frmInputValue.resx">
+      <DependentUpon>frmInputValue.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="windows\MDemo.resx">
+      <DependentUpon>MDemo.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="Modbus-slave.resx">
+      <DependentUpon>Modbus-slave.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="Properties\Resources.resx">
+      <Generator>ResXFileCodeGenerator</Generator>
+      <LastGenOutput>Resources.Designer.cs</LastGenOutput>
+      <SubType>Designer</SubType>
+    </EmbeddedResource>
+    <Compile Include="Properties\Resources.Designer.cs">
+      <AutoGen>True</AutoGen>
+      <DependentUpon>Resources.resx</DependentUpon>
+      <DesignTime>True</DesignTime>
+    </Compile>
+    <EmbeddedResource Include="windows\ProTest.resx">
+      <DependentUpon>ProTest.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="UserMQTT.resx">
+      <DependentUpon>UserMQTT.cs</DependentUpon>
+    </EmbeddedResource>
+    <EmbeddedResource Include="windows\sanchen.resx">
+      <DependentUpon>sanchen.cs</DependentUpon>
+    </EmbeddedResource>
+    <None Include="app.config" />
+    <None Include="packages.config" />
+    <None Include="Properties\Settings.settings">
+      <Generator>SettingsSingleFileGenerator</Generator>
+      <LastGenOutput>Settings.Designer.cs</LastGenOutput>
+    </None>
+    <Compile Include="Properties\Settings.Designer.cs">
+      <AutoGen>True</AutoGen>
+      <DependentUpon>Settings.settings</DependentUpon>
+      <DesignTimeSharedInput>True</DesignTimeSharedInput>
+    </Compile>
+  </ItemGroup>
+  <ItemGroup />
+  <ItemGroup>
+    <None Include="Resources\057.png" />
+  </ItemGroup>
+  <ItemGroup>
+    <BootstrapperPackage Include="Microsoft.Net.Framework.3.5.SP1">
+      <Visible>False</Visible>
+      <ProductName>.NET Framework 3.5 SP1</ProductName>
+      <Install>false</Install>
+    </BootstrapperPackage>
+  </ItemGroup>
+  <ItemGroup>
+    <WCFMetadata Include="Connected Services\" />
+  </ItemGroup>
+  <ItemGroup>
+    <Content Include="favicon.ico" />
+    <Content Include="picture\Gear_102px_1197692_easyicon.net.ico" />
+    <Content Include="Lib\LibModbus.dll" />
+    <Content Include="Lib\LibSocket.dll" />
+    <Content Include="picture\nut_128px_1101797_easyicon.net.ico" />
+    <None Include="Resources\logo.png" />
+  </ItemGroup>
+  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+  <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
+       Other similar extension points exist, see Microsoft.Common.targets.
+  <Target Name="BeforeBuild">
+  </Target>
+  <Target Name="AfterBuild">
+  </Target>
+  -->
+</Project>
\ No newline at end of file

ModbusDemo/ModbusDemo.sln

+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio 15
+VisualStudioVersion = 15.0.27703.2042
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ModbusDemo", "ModbusDemo\ModbusDemo.csproj", "{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7D83EE1F-F3D9-4592-A0ED-A0D92DCF91AB}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {A1C8BC4E-F325-41B4-8D8A-6DD96C556151}
+	EndGlobalSection
+EndGlobal

ModbusDemo/ModbusDemo/Common/ModSearch.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Net;
+using System.Net.Sockets;
+using System.Threading;
+using System.Text.RegularExpressions;
+using System.Collections;
+using System.Management;
+using System.Net.NetworkInformation;
+
+namespace ModbusDemo.Common
+{
+    class ModSearch
+    {
+        public struct DeviceInfo
+        {
+            public string ModuleName;
+            public string MacAddr;
+            public string IpAddr;
+            public string Netmask;
+            public string Gateway;
+            public bool bActive;
+        };
+
+        public UdpClient client;
+        public IPEndPoint endpoint;
+        Thread searchth;
+        ManualResetEvent mre = new ManualResetEvent(false);
+
+        public DeviceInfo m_DeviceInfo;
+        public ArrayList myHMIList = new ArrayList();
+
+        string FMAC =null;
+
+        string localip = null;
+
+        /// <summary>
+        /// 构造函数
+        /// </summary>
+        public ModSearch()
+        {
+            myHMIList.Clear();
+  
+            NetworkInterface[] nics = NetworkInterface.GetAllNetworkInterfaces();
+            foreach (NetworkInterface adapter in nics)
+            {
+                if (adapter.Name == "本地连接")  //这里是为了匹配我自己电脑网卡
+                {
+                    bool Pd1 = (adapter.NetworkInterfaceType == NetworkInterfaceType.Ethernet); //判断是否是以太网连接
+                    if (Pd1)
+                    {
+                        {
+                            IPInterfaceProperties ip = adapter.GetIPProperties();     //IP配置信息
+                            UnicastIPAddressInformationCollection ipCollection = ip.UnicastAddresses;
+                            foreach (UnicastIPAddressInformation ipadd in ipCollection)
+                            {
+                                if (ipadd.Address.AddressFamily == AddressFamily.InterNetwork)
+                                     this.localip = ipadd.Address.ToString();//获取ip
+                            }
+                        }
+                    }
+                }
+             }          
+        }
+
+        public void ThStart()
+        {
+            if (mre != null)
+                mre.Reset();
+            Console.WriteLine("搜索线程开始....");
+            searchth = new Thread(ThreadMethod);
+            searchth.IsBackground = true;
+            searchth.Start();         
+        }
+
+        public void ThStop()
+        {
+            Console.WriteLine("搜索线程结束....");
+            mre.Set();
+        }
+
+        public int HMICount()
+        {
+            return myHMIList.Count;
+        }
+
+        private void ThreadMethod()
+        {
+            byte[] sendBytes = new byte[] { 0x57, 0x54, 0x04, 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00, 0x55, 0xAA };
+            int iReadBytes = 0;
+
+            try
+            {
+               client = new UdpClient(new IPEndPoint(IPAddress.Any, 0));
+               // client = new UdpClient(new IPEndPoint(IPAddress.Parse(this.localip), 0));
+
+                endpoint = new IPEndPoint(IPAddress.Parse("255.255.255.255"), 5048);
+                client.Send(sendBytes, sendBytes.Length, endpoint);
+                Thread.Sleep(500);
+
+                byte[] recvBytes;
+                client.Client.Blocking = false;
+                while (!mre.WaitOne(500))
+                {
+                    iReadBytes = 30;
+                    int buffSizeCurrent;
+                    buffSizeCurrent = client.Client.Available;
+                    if (buffSizeCurrent > 0)
+                    {
+                        recvBytes = client.Receive(ref endpoint);
+                        iReadBytes = recvBytes.Length;
+                        DoRecvDataCallBack(recvBytes, iReadBytes);
+                    }
+                }
+            }catch
+            {
+               
+            }
+           
+        }
+
+        public Boolean DoRecvDataCallBack(byte[] pcData, int iRecvLength)
+        {
+            int i;
+            int count = 0;
+            byte[] pBuf = pcData;
+            int iDataLength = 0;
+         
+            if (iRecvLength < 8)
+                return false;
+
+            if ((pBuf[0] == (byte)0x57) && (pBuf[1] == (byte)0x54) && (pBuf[iRecvLength - 2] == (byte)0x55) && (pBuf[iRecvLength - 1] == (byte)0xAA))
+            {
+                iDataLength = (int)(pBuf[2] & 0xFF)
+                                | (int)((pBuf[3] & 0xFF) << 8)
+                                | (int)((pBuf[4] & 0xFF) << 16)
+                                | (int)((pBuf[5] & 0xFF) << 24);
+
+                if ((iDataLength >= 4) && (iRecvLength == 8 + iDataLength))
+                {                   
+                    System.Text.ASCIIEncoding asciiEncoding = new System.Text.ASCIIEncoding();
+                    m_DeviceInfo.bActive = false;
+                                      
+                    for (i = 0; i < 100; i++ )
+                    {
+                        if (asciiEncoding.GetString(pBuf, 6 + i, 1) == "\0")
+                            break;
+                        count++;
+                    }
+                   // m_DeviceInfo.ModuleName = String.Format("{0}", asciiEncoding.GetString(pBuf, 6, count));
+                    //脱机
+                    m_DeviceInfo.ModuleName = String.Format("{0}{1}{2}{3}", asciiEncoding.GetString(pBuf, 6, 1),
+                                                                                      asciiEncoding.GetString(pBuf, 7, 1),
+                                                                                        asciiEncoding.GetString(pBuf, 8, 1),
+                                                                                        asciiEncoding.GetString(pBuf, 9, 1));
+                    m_DeviceInfo.MacAddr = String.Format("{0}:{1}:{2}:{3}:{4}:{5}", pBuf[10], pBuf[11], pBuf[12], pBuf[13], pBuf[14], pBuf[15]);
+                    m_DeviceInfo.IpAddr = String.Format("{0}.{1}.{2}.{3}", pBuf[16], pBuf[17], pBuf[18], pBuf[19]);
+                    m_DeviceInfo.Netmask = String.Format("{0}.{1}.{2}.{3}", pBuf[20], pBuf[21], pBuf[22], pBuf[23]);
+                    m_DeviceInfo.Gateway = String.Format("{0}.{1}.{2}.{3}", pBuf[24], pBuf[25], pBuf[26], pBuf[27]);                  
+                    if (m_DeviceInfo.IpAddr != "0.0.0.0")
+                    {
+                        myHMIList.Add(m_DeviceInfo);
+                    }
+                   
+                    return true;
+                }
+            }
+            return false;
+        }
+    }
+}

ModbusDemo/ModbusDemo/Common/WTModbus.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Runtime.InteropServices;
+
+namespace ModbusDemo.Common
+{
+    class WTModbus
+    {
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnLibModbus", CharSet = CharSet.Unicode)]
+        public static extern uint fnLibModbus();
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadCoilStatus")]
+        public static extern int fnReadCoilStatus(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.Byte[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadInputStatus")]
+        public static extern int fnReadInputStatus(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.Char[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadHoldingReg")]
+        public static extern int fnReadHoldingReg(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.UInt16[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadInputReg")]
+        public static extern int fnReadInputReg(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.UInt16[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnWriteSingleCoil")]
+        public static extern int fnWriteSingleCoil(uint handle, ushort address, ushort state, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnWriteHoldingReg")]
+        public static extern int fnWriteHoldingReg(uint handle, ushort address, ushort state, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnWriteMultipleCoils")]
+        public static extern int fnWriteMultipleCoils(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.Char[] src, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnWriteMultipleRegs")]
+        public static extern int fnWriteMultipleRegs(uint handle, ushort address, ushort num, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.UInt16[] src, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReportSlaveID")]
+        public static extern int fnReportSlaveID(uint handle, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.Char[] src, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnMaskWriteReg")]
+        public static extern int fnMaskWriteReg(uint handle, ushort address, ushort amask, ushort omask, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnReadWriteMultipleRegs")]
+        public static extern int fnReadWriteMultipleRegs(uint handle, ushort waddress, ushort wnum, ushort raddress, ushort rnum, [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 1)] System.UInt16[] dest, byte[] Ip, ushort wTcpPort);
+        [DllImport(@"LibModbus.dll", EntryPoint = "fnLibModbusClose")]
+        public static extern void fnLibModbusClose(uint handle);
+
+        private uint hModbusHandle;
+        private System.UInt16[] dest = new System.UInt16[10] { 0, 0, 3, 4, 5, 6, 7, 8, 9, 0 };
+
+        public WTModbus()
+        {
+            this.hModbusHandle = fnLibModbus();
+        }
+
+        ~WTModbus()
+        {
+            fnLibModbusClose(hModbusHandle);
+        }
+     
+        /// <summary>
+        /// 读线圈状态
+        /// </summary>
+        /// <param name="addr">地址</param>
+        /// <param name="num">线圈数目</param>
+        /// <param name="ip">设备IP</param>
+        /// <param name="wport">端口号 默认502</param>
+        /// <param name="buf">读取结果</param>
+        /// <returns>
+        /// 0 -- no error
+        /// 1 -- illegal register address.
+        /// 2 -- illegal argument
+        /// 3 -- porting layer error
+        /// 4 -- insufficient resources
+        /// 5 -- I/O error
+        /// 6 -- protocol stack in illegal state
+        /// 7 -- timeout error occurred
+        /// 8 -- slave address error
+        /// 9 -- exception error occurred
+        /// 10-- CRC check error
+        /// 11-- send data error
+        /// 12-- receive data error
+        /// 13-- TCP connect error
+        /// 14-- close error
+        /// </returns>
+        public int ReadCoilStatus(ushort addr, ushort num, String ip, ushort wport, ref byte[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadCoilStatus(hModbusHandle, (ushort)(addr - 1), num, buf, bIp, wport);     
+            return ret;
+        }
+
+        public int ReadInputStatus(ushort addr, ushort num, String ip, ushort wport, ref char[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadInputStatus(hModbusHandle, (ushort)(addr - 1), 1, buf, bIp, 502);
+            return ret;
+        }
+
+        public int ReadHoldingReg(ushort addr, ushort num, String ip, ushort wport, ref UInt16[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadHoldingReg(hModbusHandle, (ushort)(addr - 1), num, buf, bIp, wport);
+            return ret;
+        }
+
+        public int ReadInputReg(ushort addr, ushort num, String ip, ushort wport, ref UInt16[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadInputReg(hModbusHandle, (ushort)(addr - 1), 1, dest, bIp, wport);
+            buf[0] = dest[0];
+            return ret;
+        }
+
+        public int WriteSingleCoil(ushort addr, ushort state, String ip, ushort wport)
+        {
+            int ret = 0;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnWriteSingleCoil(hModbusHandle, (ushort)(addr - 1), state, bIp, wport);
+            return ret;
+        }
+
+        public int WriteHoldingReg(ushort addr, ushort state, String ip, ushort wport)
+        {
+            int ret = 0;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnWriteHoldingReg(hModbusHandle, (ushort)(addr - 1), state, bIp, wport);
+            return ret;
+        }
+
+        public int ReadHoldingReg(ushort addr, ushort num, String ip, ushort wport, ref char[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnWriteMultipleCoils(hModbusHandle, (ushort)(addr - 1), 1, buf, bIp, wport);
+            return ret;
+        }
+
+        public int WriteMultipleRegs(ushort addr, ushort num, String ip, ushort wport, ref ushort[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnWriteMultipleRegs(hModbusHandle, (ushort)(addr - 1), num, buf, bIp, wport);
+            return ret;
+        }
+
+        public int ReportSlaveID(ushort addr, ushort num, String ip, ushort wport, ref char[] buf)
+        {
+            int ret;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReportSlaveID(hModbusHandle, buf, bIp, 502);
+            return ret;
+        }
+
+        public int MaskWriteReg(ushort addr, ushort amask, ushort omask, String ip, ushort wport)
+        {
+            int ret = 0;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnMaskWriteReg(hModbusHandle, (ushort)(addr - 1), amask, omask, bIp, wport);
+            return ret;
+        }
+
+        public int ReadWriteMultipleRegs(ushort waddr, ushort wnum, ushort raddr, ushort rnum, String ip, ushort wport, ref UInt16[] buf)
+        {
+            int ret = 0;
+            byte[] bIp = Encoding.Unicode.GetBytes(ip);
+            ret = fnReadWriteMultipleRegs(hModbusHandle, (ushort)(waddr - 1), wnum, raddr, rnum, buf, bIp, wnum);
+            return ret;
+        }
+    }
+}

ModbusDemo/ModbusDemo/MDemo.cs

+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Data;
+using System.Drawing;
+using System.Linq;
+using System.Text;
+using System.Windows.Forms;
+using ModbusDemo.Common;
+using System.Threading;
+using System.Text.RegularExpressions;
+
+namespace ModbusDemo
+{
+    public partial class MDemo : Form
+    {
+
+        WTModbus ReadTest;
+        const ushort address = 17;
+        const ushort num = 6;
+        const ushort DevicePort = 502;
+        string DeviceIP;
+
+        ManualResetEvent showmre = new ManualResetEvent(false);
+        public delegate void invokeDelegate();
+
+        public MDemo()
+        {
+            InitializeComponent();
+            ReadTest = new WTModbus();
+        }
+
+        Thread t_ReadCoil;
+        private void TestBtn_Click(object sender, EventArgs e)
+        {
+            this.TestBtn.Enabled = false;        
+            if (this.IPsetBox.Text != "")
+            {
+                DeviceIP = this.IPsetBox.Text;
+            }
+            else
+            {
+                MessageBox.Show("请检查IP输入是否正确");
+                this.TestBtn.Enabled = true;
+                return;
+            }
+        
+            if (showmre != null)
+            {
+                showmre.Reset();
+            }
+            t_ReadCoil = new Thread(ReadCoilProc);
+            t_ReadCoil.IsBackground = true;
+            t_ReadCoil.Start();                 
+        }
+       
+        private void ReadCoilProc(object obj)
+        {                    
+            short allval;                    
+            byte[] temp = new byte[6];
+            int ret;
+
+            while (!showmre.WaitOne(500))
+            {
+                //读线圈
+                ret = ReadTest.ReadCoilStatus(address, num, DeviceIP, DevicePort, ref temp);
+                allval = BitConverter.ToInt16(temp, 0);
+
+                invokeDelegate update = () =>
+                {
+                    foreach (Control control in this.CoilBox.Controls)
+                    {
+                        if(control is PictureBox)
+                        {
+                            if ((allval >> Convert.ToUInt16((control as PictureBox).Tag) & 0x1) == 1)
+                            {
+                                (control as PictureBox).BackColor = Color.Green;
+                            }
+                            else
+                            {
+                                (control as PictureBox).BackColor = Color.Black;
+                            }
+                        }                      
+                    }
+                };
+                Invoke(update);
+            }
+                               
+        }
+
+        private void stopbtn_Click(object sender, EventArgs e)
+        {
+            this.TestBtn.Enabled = true;
+            if (showmre != null)
+                showmre.Set();
+
+            foreach (Control control in this.CoilBox.Controls)
+            {
+                if (control is PictureBox)
+                {
+                    (control as PictureBox).BackColor = Color.Black;                    
+                }
+            }
+        }
+    }
+}

ModbusDemo/ModbusDemo/MDemo.resx

+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+</root>
\ No newline at end of file