根据鼠标起点和落点判断鼠标操作

virtual BOOL PreTranslateMessage(MSG* pMsg);

BOOL CDlg::PreTranslateMessage(MSG* pMsg)
{
// TODO: 在此添加专用代码和/或调用基类
if(WM_LBUTTONDOWN== pMsg->message)
{
if (m_bLeftButtonDown==FALSE)
{
int xPos = LOWORD(pMsg->lParam);
int yPos = HIWORD(pMsg->lParam);

m_LastPoint.x=xPos;
m_LastPoint.y=yPos;
::ClientToScreen(pMsg->hwnd,&m_LastPoint);
m_bLeftButtonDown=TRUE;
}
}else if (WM_LBUTTONUP==pMsg->message)
{
if (m_bLeftButtonDown)
{
int xPos = LOWORD(pMsg->lParam);
int yPos = HIWORD(pMsg->lParam);
m_CrrentPoint.x=xPos;
m_CrrentPoint.y=yPos;
::ClientToScreen(pMsg->hwnd,&m_CrrentPoint);
m_bLeftButtonDown=FALSE;
DoYouThings();//处理你想处理的动作
}
}
return CDialogEx::PreTranslateMessage(pMsg);
}