procedure WMSize (var Message: TWMSize);  message WM_SIZE;
 
 
参数说明
wParam:
Specifies the type of resizing requested.
通常用来向别的窗口发送消息时,需要指定的附加信息
| 
 Value 
 | 
 Meaning 
 | 
| 
 SIZE_MAXHIDE 
 | 
 Message is sent to all pop-up windows when some other window is maximized. 
 | 
| 
 SIZE_MAXSHOW 
 | 
 Message is sent to all pop-up windows when some other window has been restored to its former size. 
 | 
| 
 SIZE_MINIMIZED 
 | 
 The window has been minimized. 
 | 
| 
 Value 
 | 
 Meaning 
 | 
| 
 SIZE_RESTORED 
 | 
 The window has been resized, but neither the SIZE_MINIMIZED nor SIZE_MAXIMIZED value applies. 
 | 
lParam:
The low-order word of lParamspecifies the new width of the client area.
The high-order word of lParam specifies the new height of the client area.
note:
lParam和GetClientRect的功能一样,有时候WM_SIZE的效率要比使用GetClientRect高. 可以在程序中使用WM_SIZE来保存Client area的大小方便以后使用.
WM_SIZE后于WM_CREATE消息!!在窗口被创建时的顺序!
WM_SIZE附带的信息:
WM_SIZE
fwSizeType = wParam; // resizing flag
nWidth = LOWORD(lParam); // width of client area
nHeight = HIWORD(lParam); // height of client area
告诉我们Windows处理窗口大小变化后新窗口客户区的大小.
Message Cracker
void Cls_OnSize(HWND hwnd, UINT state, int cx, int cy)
...{
//do ...
}
参数cx,cy是新窗口客户区的大小!宽度和高度
static UINT cx,cy;
switch (message)
{
case WM_SIZE:
cx=LOWORD(lParam);
cy=HIWORD(lParam);
break;
 
http://www.cnblogs.com/toosuo/p/3387827.html
WM_SIZE后于WM_CREATE消息!!在窗口被创建时的顺序!
原文:http://www.cnblogs.com/findumars/p/7127107.html