RECT rt;
SystemParametersInfo(SPI_GETWORKAREA, 0, &rt, 0);
//任务栏在下面的高度
int y = ::GetSystemMetrics(SM_CYSCREEN)-rt.Height();
//上面
y = rt.top;
//左
y = rt.left;
//右
y = ::GetSystemMetrics(SM_CXSCREEN)-rt.Width();
HWND hwnd = ::FindWindow("Shell_TrayWnd","");
RECT rect;
::GetWindowRect(hwnd, &rect);
int nHeight = rect.bottom - rect.top;