DUILib 中的 caption="x1,y1,x2,y2"
x1 距离左边界的距离；rcCaption.left
y1 距离上边界的距离; rcCaption.top
x2 距离右边界的距离；rcCaption.right
y2 距离上边界的距离； rcCaption.bottom
rcClient 为客户区域大小
标题栏范围:
"rcClient.left + rcCaption.left（左边界坐标）, rcCaption.top(上边界坐标),
rcClient.right - rcCaption.right（右边界坐标）， rcCaption.bottom（下边界坐标）“
1 RECT rcCaption = m_PaintManager.GetCaptionRect();
2 if( pt.x >= rcClient.left + rcCaption.left && pt.x < rcClient.right - rcCaption.right
3 && pt.y >= rcCaption.top && pt.y < rcCaption.bottom ) {
4 CControlUI* pControl = static_cast<CControlUI*>(m_PaintManager.FindControl(pt));
5 if( pControl && _tcsicmp(pControl->GetClass(), _T("ButtonUI")) != 0 &&
6 _tcsicmp(pControl->GetClass(), _T("OptionUI")) != 0 &&
7 _tcsicmp(pControl->GetClass(), _T("TextUI")) != 0 )
8 return HTCAPTION;
9 }