Question

VC如何得到鼠标焦点所在的控件ID

Answer 1

楼上的，GetFocus看翻译返回的应该是键盘的焦点吧，具体未测试。
现提供一种方法获取当前鼠标所在位置的控件ID.
如下(Win32):
POINT pt;
GetCursorPos(&pt);
HWND hWnd = WindowFromPoint(pt);
ScreenToClinet(hWnd,&pt);
//得到窗体的控件句柄
HWND hControlWnd = ChildWindowFromPoint(hWnd,pt);
UINT uId=GetDlgCtrlID(hControlWnd);

Answer 2

自己设定一个类内的成员变量usigned int OldID用于记录当前焦点控件的ID，等到下一个控件获得焦点的时候，OldID中的值就是前一个焦点的ID

Answer 3

MFC::
CWnd *pWnd = GetFocus();
if(pWnd == NULL)
;//no focus
else
UINT nID = pWnd->GetDlgCtrlID();

SDK:
HWND hWnd = ::GetFocus();
if(hWnd == NULL)
;//no focus
else
UINT nID = ::GetDlgCtrlID(hWnd);

GetFocus: The return value is the handle to the window with the keyboard focus. If the calling thread's message queue does not have an associated window with the keyboard focus, the return value is NULL.