進程間的通信

using System.Runtime.InteropServices;//添加引用

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

const int WM_COPYDATA = 0x004A;//WINDOWS信息

[DllImport("User32.dll",EntryPoint="SendMessage")]
  private static extern int SendMessage(
   int hWnd, // 向接收信息的進程句柄
   int Msg, // 消息

   int wParam, // 消息參數
   ref COPYDATASTRUCT lParam // 消息參數
   );

public void send()

{

string msg = "測試";

byte[] sarr = System.Text.Encoding.Default.GetBytes(msg );
       int len = sarr.Length;
       COPYDATASTRUCT cds;
       cds.dwData = (IntPtr) 100;
       cds.lpData = msg;
       cds.cbData = len + 1;
       SendMessage(int.Parse(Ptrstr), WM_COPYDATA, 0, ref cds);

}

//接收進程

  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);
         //mystr.lpData 就是傳近來的字符串!
          break;
    default:
     base.DefWndProc(ref m);
     break;
   }
  }