WM_COPYDATA实现进程间数据共享

矫情吗；* 2022-06-17 02:42 198阅读 0赞

本文转自： [http://www.cppblog.com/TechLab/archive/2005/12/30/2272.html][http_www.cppblog.com_TechLab_archive_2005_12_30_2272.html]

实现进程间数据共享除了常用的内存文件映射外，对于一些非文件的数据共享可以直接使用消息WM\_COPYDATA。  
如果需要在进程A传递数据到进程B，简单的实现如下：  
在进程A中：  
CString strDataToSend = \_T( "Hello" ); //需要传递的数据  
HWND hWndReceived; //进程B的接收数据窗口对象  
//COPYDATASTRUCT结构是WM\_COPYDATA传递的数据结构对象  
COPYDATASTRUCT cpd;  
cpd.dwData = 0;  
cpd.cbData = strDataToSend.GetLength(); //传递的数据长度  
cpd.lpData = (void\*)strDataToSend.GetBuffer(cpd.cbData); //传递的数据地址  
SendMessage( hWndReceived, WM\_COPYDATA, 0, (LPARAM) & cpd );  
strDataToSend.ReleaseBuffer();  
  
在目标进程B中，先手动建立好函数声明和实现  
BEGIN\_MESSAGE\_MAP(CMyWnd, CWnd)  
//\{ \{AFX\_MSG\_MAP(CMyWnd)  
ON\_WM\_COPYDATA()  
//\}\}AFX\_MSG\_MAP  
END\_MESSAGE\_MAP()

映射函数：  
BOOL CMyWnd::OnCopyData(CWnd\* pWnd, COPYDATASTRUCT\* pCopyDataStruct)  
\{  
　　　CString strRecievedText = (LPCSTR) (pCopyDataStruct->lpData);  
　　　return CMyWnd::OnCopyData(pWnd, pCopyDataStruct);  
\}  
  
还可以参考MSDN文章Using Data Copy  
[http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winui/winui/windowsuserinterface/dataexchange/datacopy/usingdatacopy.asp][http_msdn.microsoft.com_library_default.asp_url_library_en-us_winui_winui_windowsuserinterface_dataexchange_datacopy_usingdatacopy.asp]

[http_www.cppblog.com_TechLab_archive_2005_12_30_2272.html]: http://www.cppblog.com/TechLab/archive/2005/12/30/2272.html
[http_msdn.microsoft.com_library_default.asp_url_library_en-us_winui_winui_windowsuserinterface_dataexchange_datacopy_usingdatacopy.asp]: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/winui/winui/windowsuserinterface/dataexchange/datacopy/usingdatacopy.asp