C# PC版微信消息监听自动回复的实现方法

/// 消息主要接受程序
  /// </summary>
  /// <param name="m"></param>
  protected override void DefWndProc(ref Message m)
  {
   switch (m.Msg)
   {
    case 74: //74代表WM_COPYDATA     
     string message = "";
     int f = (int)m.WParam;
     try
     {
      COPYDATASTRUCT2 cds2 = (COPYDATASTRUCT2)m.GetLParam(typeof(COPYDATASTRUCT2));
      message = Marshal.PtrToStringAnsi(cds2.lpData);
     }
     catch (Exception e)
     {
      LogHelper.WriteLog("解析微信消息报错", e); //发文字带空格报错
     }
 
     switch (f)
     {
      //登录时解析用户信息
      case 10003:
       try
       {
        if (!string.IsNullOrEmpty(message))
        {
         MessageHandler.Parse10003(message);
        }
        this.Invoke(new MethodInvoker(() => { richTextBox1.AppendText("【" + MessageHandler.myUserInfo.UserName + "】登录成功!\r\n"); }));
       }
       catch (Exception e1)
       {<br>        LogHelper.WriteLog("解析微信登录用户信息错误", e1);
       }
       return;<br>
      //文字,图片,视频,文件 解析
      case 10012:
       try
       {
        if (message.Contains("msgtyp:"))
        {
         string[] datas = Regex.Split(message, "msgtyp:", RegexOptions.IgnoreCase);
         if (datas.Count() >= 2)
         {
          string msgtyp = datas[1].Split(',')[0];
          switch (msgtyp.Replace(" ", ""))
          {
           case "1": //文字
 
            if (message.Contains("[群-->]") && message.Contains("[消息内容-->]"))
            {
             string word = "";  //发送内容
 
             //取消息内容
             string[] wordArr = Regex.Split(message, @"消息内容-->]", RegexOptions.IgnoreCase);
 
             string[] aa = wordArr[1].Split(new string[] { "||" }, StringSplitOptions.RemoveEmptyEntries);
             if (aa[0].StartsWith(" "))
             {
              word = aa[0].Substring(1);
             }
             else
             {
              word = aa[0];
             }
 
             string groupId = WxMessageHelper.GetChatRoom(message);
             string groupName = WxMessageHelper.GetGroupName(message);
             string nickName = WxMessageHelper.GetNickName(message);
             string memberpuid = WxMessageHelper.GetWxId(message);
 
             List<string> data = ReadFile();
             foreach(var str in data)
             {
              string key = str.Split(';')[0];
              string value = str.Split(';')[1];
 
              if (word.Contains(key))
              {
               string[] sarr = Regex.Split(word, str, RegexOptions.IgnoreCase);
 
               this.Invoke(new MethodInvoker(() => { richTextBox1.AppendText("【" + nickName + "】在【" + groupName + "】发送了关键词消息："+ sarr[0]);
                richTextBox1.AppendTextColorful(key, Color.Red, false);
                richTextBox1.AppendText(key + "\r\n");
               }));
 
               //调用回复
               SendMessage(groupId + "||" + value, 20001);
              }
             }
            }
 
            break;
          }
         }
        }
       }
       catch (Exception e2)
       {
        this.Invoke(new MethodInvoker(() => { richTextBox1.AppendText(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + "10012 : 解析微信群信息错误\r\n\r\n"); }));
       }
       break;
      default:
       break;
     }
     //消息内容 cds.lpData
     break;
 
    default:
     base.DefWndProc(ref m);
     break;
   }
  }

/// <summary>
  /// 发送消息
  /// </summary>
  /// <param name="message">消息内容</param>
  /// <param name="wParam">通讯号</param>
  /// <returns></returns>
  private int SendMessage(string message, int wParam)
  {
   byte[] sarr = System.Text.Encoding.Default.GetBytes(message);
   int len = sarr.Length;
   COPYDATASTRUCT cds;
   cds.dwData = (IntPtr)Convert.ToInt16(1); //可以是任意值
   cds.cbData = len + 1; //指定lpData内存区域的字节数
   cds.lpData = message; //发送给目标窗口所在进程的数据
   return myapi.SendMessage(common.微信句柄, 74, wParam, ref cds); //74代表WM_COPYDATA
  }

[StructLayout(LayoutKind.Sequential, Size=1)]
public struct myapi
{
 [DllImport("user32", EntryPoint="SetWindowLong")]
 public static extern int SetWindowLongA(int hwnd, int nIndex, int dwNewLong);
 [DllImport("User32.dll")]
 public static extern int SendMessage(int hwnd, int msg, int wParam, ref COPYDATASTRUCT IParam);
 [DllImport("User32.dll")]
 public static extern int FindWindow(string lpClassName, string lpWindowName);
}