RegisterWindowMessage中的BroadcastSystemMessage如何处理?
 

我想用BroadcastSystemMessage来在两个进程之间通讯,我从一个进程发送了一个
用RegisterWindowMessage注册过的消息,但在目的进程中却没有收到该消息.

我认为你应该在两个进程的最高级窗口中都注册该消息.请看下例:

static UINT sBroadcastCommand = ::RegisterWindowMessage( _T("BroadcastCommand"));

BEGIN_MESSAGE_MAP( Gui_Top_Level_MainFrame, Gui_MainFrame )
    ON_REGISTERED_MESSAGE( sBroadcastCommand, onBroadcastCommand )
END_MESSAGE_MAP()

LRESULT Gui_MainFrame :: onBroadcastCommand( UINT aMsg, LPARAM lParam )
{
    your code...
}
然后发送进行应该包含:
While the sending process would contain:

static UINT sBroadcastCommand = ::RegisterWindowMessage( _T("BroadcastCommand"));

void Someclass :: someMethod( void )
    {
    ::PostMessage( (HWND)HWND_BROADCAST,
                                sBroadcastCommand, 0,
                                yourMessageId );
    }