using Microsoft.WindowsCE.Forms; public partial class MsgForm : Form {         [DllImport("coredll.dll", EntryPoint = "RegisterWindowMessage", SetLastError = true)]         private static extern uint RegisterWindowMessage(string lpString);         private uint msgUid = RegisterWindowMessage("MESSAGE_UID"); 　　　public static int MSG_BROADCAST = 0xFFFF; 　　　private void SendMessage(object sender)         {             Message msg = Message.Create((IntPtr)MSG_BROADCAST, (int)msgUid , IntPtr.Zero, IntPtr.Zero);             MessageWindow.SendMessage(ref msg);         } }    }

using Microsoft.WindowsCE.Forms; public class MsgWindow : MessageWindow {     [DllImport("coredll.dll", EntryPoint = "RegisterWindowMessage", SetLastError = true)]     private static extern uint RegisterWindowMessage(string lpString);     private uint msgUid = RegisterWindowMessage("MESSAGE_UID");     protected override void WndProc(ref Message msg)     {         if (msg.Msg == msgUid )        {             //handle the message.        }     } }

public partial class MsgForm : Form {     private MsgWindow MsgWin;     public MsgForm()     {         //pass the form reference to messagewindow         this.MsgWin = new MsgWindow(this);     } } public class MsgWindow : MessageWindow {      private MsgForm msgForm; 　　public MsgWindow(MsgForm msgForm)      {             this.msgForm= msgForm;      } 　　protected override void WndProc(ref Message msg) 　　 {     　　if (msg.Msg == msgUid )    　　　{ 　　　　　　 //call form to handle the message.        　　msgForm.HandleMsg(); 　　　　 } 　　 } }

public struct COPYDATASTRUCT {     public int dwData;     public int cbData;     public IntPtr lpData; }     class cMsgStrings     {         const int LMEM_FIXED = 0x0000;         const int LMEM_ZEROINIT = 0x0040;         const int LPTR = (LMEM_FIXED | LMEM_ZEROINIT);         const int WM_COPYDATA = 0x004A;         [DllImport("coredll.dll")]         public static extern IntPtr LocalAlloc(int flag, int size);         [DllImport("coredll.dll")]         public static extern IntPtr LocalFree(IntPtr p);         [DllImport("coredll.dll")]         public static extern int SendMessageW(IntPtr hWnd, int Msg, IntPtr wParam, IntPtr lParam);         public static IntPtr AllocHGlobal(int cb)         {             IntPtr hMemory = new IntPtr();             hMemory = LocalAlloc(LPTR, cb);             return hMemory;         }         public static void FreeHGlobal(IntPtr hMemory)         {             if (hMemory != IntPtr.Zero)                 LocalFree(hMemory);         }         public static void SendMsgString(IntPtr hWndDest, string sScript)         {             COPYDATASTRUCT oCDS = new COPYDATASTRUCT();             oCDS.cbData = (sScript.Length + 1) * 2;             oCDS.lpData = LocalAlloc(LPTR, oCDS.cbData);             Marshal.Copy(sScript.ToCharArray(), 0, oCDS.lpData, sScript.Length);             oCDS.dwData = 1;             IntPtr lParam = AllocHGlobal(oCDS.cbData);             Marshal.StructureToPtr(oCDS, lParam, false);             SendMessageW(hWndDest, WM_COPYDATA, IntPtr.Zero, lParam);             LocalFree(oCDS.lpData);             FreeHGlobal(lParam);         }     } //send the message with string private void button1_Click(object sender, EventArgs e) {     unsafe     {         cMsgStrings.SendMsgString((IntPtr)MSG_BROADCAST, textBoxMsg.Text);     } }

public class MsgWindow : MessageWindow {     const int WM_COPYDATA = 0x004A;     private FormReceiver msgForm;     public MsgWindow(FormReceiver msgForm)     {         this.msgForm = msgForm;     }     protected override void WndProc(ref Message msg)     {         if (msg.Msg == WM_COPYDATA)         {             string str = GetMsgString(msg.LParam);             msgForm.HandleMsg(str);         }     }     public static string GetMsgString(IntPtr lParam)     {         if (lParam != IntPtr.Zero)         {             COPYDATASTRUCT st = (COPYDATASTRUCT)Marshal.PtrToStructure(lParam, typeof(COPYDATASTRUCT));             string str = Marshal.PtrToStringUni(st.lpData);             return str;         }         else         {             return null;         }     } }


http://www.cnblogs.com/procoder/archive/2009/03/16/1413176.html

http://iwoohaha.tistory.com/90