if(Agentdata.m_capwnd==NULL) 
           return FALSE;
capCaptureStop(Agentdata.m_capwnd    
capCaptureAbort(Agentdata.m_capwnd)
       Sleep(500);
        capSetCallbackOnVideoStream(Agentdata.m_capwnd, NULL);
           Sleep(300); // This delay is important...
BOOL ret;
            ret=(capDriverDisconnect(Agentdata.m_capwnd));
 if (ret==FALSE)
  {
AfxMessageBox("CLOSE FAIL");
  }
Agentdata.m_capwnd=NULL;
return TRUE;
就是这一段,按f10的时候,ret为1,按f5的时候,ret为0
capDriverDisconnect(hwnd)时一个bool型的,成功返回1,不成功返回0
可有人知道是为何?