限制視窗在螢幕範圍內移動（不能移到螢幕外）

限制視窗在螢幕範圍內移動（不能移到螢幕外）

響應WM_WINDOWPOSCHANGING訊息

afx_msg void OnWindowPosChanging(WINDOWPOS FAR* lpwndpos);
ON_WM_WINDOWPOSCHANGING()

void CMoveWindowDlg::OnWindowPosChanging(WINDOWPOS FAR* lpwndpos)
{
 CDialog::OnWindowPosChanging(lpwndpos);

 int cx = GetSystemMetrics(SM_CXSCREEN);
 int cy = GetSystemMetrics(SM_CYSCREEN);
 
 CRect rect(0 ,0, cx, cy);
 if(lpwndpos->x < rect.left)
  lpwndpos->x = rect.left;

 if(lpwndpos->y < rect.top)
  lpwndpos->y = rect.top;

 if(lpwndpos->x + lpwndpos->cx > rect.right)
  lpwndpos->x = rect.right - lpwndpos->cx;

 if(lpwndpos->y + lpwndpos->cy > rect.bottom)
  lpwndpos->y = rect.bottom - lpwndpos->cy;
 

}