c#进程间通信（Inter-Process Communication）

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 System.Runtime.InteropServices;  //for DllImport

namespace send
{
    public partial class Form1 : Form
    {
        [DllImport("User32.dll", EntryPoint = "SendMessage")]
       // private static extern int SendMessage(int hWnd, int msg, int wParam, int lParam);       //发送消息
        private static extern int SendMessage(int hWnd, int msg, int wParam, ref COPYDATASTRUCT lParam);   
        [DllImport("User32.dll", EntryPoint = "FindWindow")]
        private static extern int FindWindow(string lpClassName, string lpWindowName);      //获取另一个进程的窗口句柄

        const int WM_COPYDATA = 0x004A;

        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int hWnd = FindWindow(null, @"Receive");
            string message = "你好消息成功发送！";
            int i = message.Length;
            byte[] sarr = System.Text.Encoding.Default.GetBytes(message);
            COPYDATASTRUCT cds;
            cds.dwData = (IntPtr)100;
            cds.lpData = message;
            cds.cbData = sarr.Length+1;         //此值错误会引发接收端崩溃
            SendMessage(hWnd, WM_COPYDATA, 0, ref cds);
        }
    }
    public struct COPYDATASTRUCT
    {
        public IntPtr dwData;
        public int cbData;
        [MarshalAs(UnmanagedType.LPStr)]
        public string lpData;
    }
}

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 System.Runtime.InteropServices;  //for  MarshalAs


namespace receive
{
    public partial class Receive : Form
    {
        const int WM_COPYDATA = 0x004A;
        const int WM_MYSYMPLE = 0x005A;

        public Receive()
        {
            InitializeComponent();
        }
        protected override void DefWndProc(ref System.Windows.Forms.Message m)
        {
            switch (m.Msg)
            {
                case WM_COPYDATA:
                    COPYDATASTRUCT myStr = new COPYDATASTRUCT();
                    Type myType = myStr.GetType();
                    myStr = (COPYDATASTRUCT)m.GetLParam(myType);    //m中获取LParam参数以myType类型的方式，让后转换问结构体。
                    label1.Text = myStr.lpData;
                    break;
                default:
                    base.DefWndProc(ref m);
                    break;
            }
        }

    }
    public struct COPYDATASTRUCT
    {
        public IntPtr dwData;
        public int cbData;
        [MarshalAs(UnmanagedType.LPStr)]
        public string lpData;
    }
}