當主窗口的客戶區部分大小改變時，我們的應用程序將接收到
WM_SIZE
消息。當然該窗口第一次顯示時，我們也將接收到該消息。要接收到該消息，主窗口必須有
CS_VREDRAW
和
CS_HREDRAW
風格。我們應該把縮放編輯控件的動作放到此處。我們要把編輯控件變成和我們的窗口客戶區一樣大，所以先得要得到父窗口客戶區的大小。這些值包含在參數
lParam
中，
lParam
的高字部分是客戶區的高，底字部分是客戶區的寬。然后我們調用
MoveWindow
函數來重新調整編輯控件的大小，該函數不僅能夠移動窗口的位置，而且能夠改變窗口的大小。
.ELSEIF uMsg==WM_SIZE
??mov eax,lParam????????????? ;低16位寬，高16位高
??mov edx,eax
??shr edx,16????????????????? ;IParam邏輯右移16位，保留高16位，即高
??and eax,0ffffh????????????? ;高16位清0，保留低16位，即寬
??invoke MoveWindow,hwndEdit,0,0,eax,edx,TRUE
WM_SIZE
The WM_SIZE message is sent to a window after its size has changed.
A window receives this message through its WindowProc function.
LRESULT CALLBACK WindowProc(
HWND hwnd, // handle to window
UINT uMsg, // WM_SIZE
WPARAMwParam, // resizing flag
LPARAMlParam // client area
);
Parameters
-
wParam
- Specifies the type of resizing requested. This parameter can be one of the following values.
| Value | Meaning |
|---|
| SIZE_MAXHIDE | Message is sent to all pop-up windows when some other window is maximized. |
| SIZE_MAXIMIZED | The window has been 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. |
| SIZE_RESTORED | The window has been resized, but neither the SIZE_MINIMIZED nor SIZE_MAXIMIZED value applies. |
-
lParam
- The low-order word of lParam specifies the new width of the client area.
The high-order word of lParam specifies the new height of the client area.
Return Values
If an application processes this message, it should return zero.