怎么我的钩子只在当前窗口为桌面时有效？


if (wParam==VK_CONTROL)//||(wParam==VK_RETURN)||(wParam>=0x2f ) &&(wParam<=0x100)) 

{    

if(nCode == HC_ACTION && (lParam & 0xA0000000) == 0)

       
{
hwndForeground=::GetForegroundWindow();
       dwCurrentThreadId=::GetCurrentThreadId();
   dwWindowThreadId=::GetWindowThreadProcessId(hwndForeground, NULL);
   AttachThreadInput(dwWindowThreadId,dwCurrentThreadId,true);
   hwndForeground=GetFocus(); 
  AttachThreadInput(dwWindowThreadId,dwCurrentThreadId,false);
   PostMessage(hwndForeground,WM_RBUTTONUP,MK_RBUTTON,0);
   PostMessage(hwndForeground,WM_LBUTTONUP,MK_LBUTTON,0);    
}
 return 1;