昨天写了MoveWindow函数，今天又要写SetWindowPos函数，因为MoveWindow确实不好，浪费了差不多一天时间。。。对于主窗口，选择了Center属性就可以移动位置，不选就不行；窗口资源过大也不能移动；改变后窗口的尺寸大于等于屏幕尺寸的话，在它上面DoModal出来的新窗口不能移动。。原来，使用MoveWindow移动对话框位置似乎有很苛刻的条件，一不小心就原地不动了，而且我也实在琢磨不透这样的条件，网上也没有查处来。今天用了SetWindowPos后，才发现，果然好用！

Parameters

pWndInsertAfter

Identifies the CWnd object that will precede this CWnd object in the Z-order. This parameter can be a pointer to a CWnd or a Pointer to one of the following values:

• wndBottom   Places the window at the bottom of the Z-order. If this CWnd is a topmost window, the window loses its topmost status; the system places the window at the bottom of all other windows.
• wndTop   Places the window at the top of the Z-order.
• wndTopMost   Places the window above all nontopmost windows. The window maintains its topmost position even when it is deactivated.
• wndNoTopMost   Repositions the window to the top of all nontopmost windows (that is, behind all topmost windows). This flag has no effect if the window is already a nontopmost window.

nFlags

Specifies sizing and positioning options. This parameter can be a combination of the following: 常用的是SWP_SHOWWINDOW

注意：
    这里的坐标参数用的是Client坐标，对于子窗口用的是其父窗口的坐标系。然而对于用DoModal()弹出的窗口，如果在资源属性里没有选择Child属性的话，它的父窗口是DeskTop，而不是调用DoModal()的窗口。