WM_NCLBUTTONDOWN+HTCAPTION消息移动一个窗口

 使用WM_NCLBUTTONDOWN+HTCAPTION消息移动一个窗口。
我在我的对话框中这样
void CMyDialog::OnLButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default

/*拖动标题栏之外任何位置都移动窗口*/
PostMessage(WM_NCLBUTTONDOWN, HTCAPTION, MAKELPARAM(point.x, point.y));

  //让另一个窗口也跟随我的对话框移动
::PostMessage(m_wndInfo.m_hWnd, WM_NCLBUTTONDOWN, HTCAPTION, MAKELPARAM(point.x, point.y));

CDialog::OnLButtonDown(nFlags, point);
}