C# SendMessage 进程通信发送字符串

最新推荐文章于 2025-05-07 14:28:57 发布

Ds萝卜

最新推荐文章于 2025-05-07 14:28:57 发布

阅读量2.3k

点赞数 6

分类专栏： C#笔记

C#笔记专栏收录该内容

11 篇文章

订阅专栏

本文介绍了一种使用C#实现的进程间通信方法，通过发送和接收自定义的消息结构体来实现不同进程间的简单数据交换。发送方通过查找目标窗口并发送特定的消息值和数据，接收方则监听特定的消息值来获取数据。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

c# 发送者

using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace sendmessageC1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        /// <summary>
        /// 定义结构体
        /// </summary>
        public struct COPYDATASTRUCT
        {
            public IntPtr dwData; //可以是任意值
            public int cbData;    //指定lpData内存区域的字节数
            [MarshalAs(UnmanagedType.LPStr)]
            public string lpData; //发送给目录窗口所在进程的数据
        }

        /// <summary>
        /// 查找窗口
        /// </summary>
        /// <param name="lpClassName">窗口类名</param>
        /// <param name="lpWindowName">窗口标题</param>
        /// <returns></returns>
        [DllImport("User32.dll", EntryPoint = "FindWindow")]
        private static extern int FindWindow(string lpClassName, string lpWindowName);

        /// <summary>
        /// 发送消息
        /// </summary>
        /// <param name="hWnd">窗口句柄</param>
        /// <param name="Msg">消息值</param>
        /// <param name="wParam">参数一</param>
        /// <param name="lParam">参数二</param>
        /// <returns></returns>
        [DllImport("User32.dll", EntryPoint = "SendMessage")]
        private static extern int SendMessage(int hWnd, int Msg, int wParam, ref COPYDATASTRUCT lParam);
   
        /// <summary>
        /// 定义消息值
        /// </summary>
        private const int WM_COPYDATA = 0x004A; //必须是这个数值，不能更改


        private void button1_Click(object sender, EventArgs e)
        {
            int hWnd = FindWindow(null, "消息接受者");
            if (hWnd == 0)
            {
                MessageBox.Show("未找到消息接受者！");
            }
            else
            {
                string sendString = textBox1.Text; //发送内容
                byte[] sarr = System.Text.Encoding.Default.GetBytes(sendString);
                int len = sarr.Length;
                COPYDATASTRUCT cds;
                cds.dwData = (IntPtr)0;
                cds.cbData = len + 1;
                cds.lpData = sendString;
                SendMessage(hWnd, WM_COPYDATA, 0, ref cds);
            }
        }

    }
}

c# 接收者

using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace sendmessageC2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        /// <summary>
        /// 定义结构体
        /// </summary>
        public struct COPYDATASTRUCT
        {
            public IntPtr dwData; //可以是任意值
            public int cbData;    //指定lpData内存区域的字节数
            [MarshalAs(UnmanagedType.LPStr)]
            public string lpData; //发送给目录窗口所在进程的数据
        }

        /// <summary>
        /// 定义消息值
        /// </summary>
        private static int WMA_InterPro = 0x004A;

        protected override void DefWndProc(ref Message m)
        {
            if (m.Msg == WMA_InterPro)
            {
                COPYDATASTRUCT cds = new COPYDATASTRUCT();
                Type t = cds.GetType();
                cds = (COPYDATASTRUCT)m.GetLParam(t);
                string receiveInfo = cds.lpData; //接收内容
                label1.Text = receiveInfo;
            }
            else
            {
                base.DefWndProc(ref m);
            }
        }
    }
}