windows 消息机制的学习

概述

链接1：http://www.cppblog.com/suiaiguo/archive/2009/07/18/90412.html

链接2：http://www.cnblogs.com/findumars/p/3948427.html

代码框架

#include <windows.h>

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PSTR szCmdLine, int iCmdShow)
{
     static TCHAR szAppName[] = TEXT ("HelloWin") ;
     HWND         hwnd ;
     MSG          msg ;
     WNDCLASS     wndclass ;

     wndclass.style         = CS_HREDRAW | CS_VREDRAW ;
     wndclass.lpfnWndProc   = WndProc ;
     wndclass.cbClsExtra    = 0 ;
     wndclass.cbWndExtra    = 0 ;
     wndclass.hInstance     = hInstance ;
     wndclass.hIcon         = LoadIcon (NULL, IDI_APPLICATION) ;
     wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW) ;
     wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
     wndclass.lpszMenuName  = NULL ;
     wndclass.lpszClassName = szAppName ;

     if (!RegisterClass (&wndclass))
     {
          MessageBox (NULL, TEXT ("This program requires Windows NT!"), 
                      szAppName, MB_ICONERROR) ;
          return 0 ;
     }
     hwnd = CreateWindow (szAppName,                  // window class name
                          TEXT ("The Hello Program"), // window caption
                          WS_OVERLAPPEDWINDOW,        // window style
                          CW_USEDEFAULT,              // initial x position
                          CW_USEDEFAULT,              // initial y position
                          CW_USEDEFAULT,              // initial x size
                          CW_USEDEFAULT,              // initial y size
                          NULL,                       // parent window handle
                          NULL,                       // window menu handle
                          hInstance,                  // program instance handle
                          NULL) ;                     // creation parameters
     
     ShowWindow (hwnd, iCmdShow) ;
     UpdateWindow (hwnd) ;
     
     while (GetMessage (&msg, NULL, 0, 0))
     {
          TranslateMessage (&msg) ;
          DispatchMessage (&msg) ;
     }
     return msg.wParam ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
     HDC         hdc ;
     PAINTSTRUCT ps ;
     RECT        rect ;
     
     switch (message)
     {
     case WM_CREATE:
          PlaySound (TEXT ("hellowin.wav"), NULL, SND_FILENAME | SND_ASYNC) ;
          return 0 ;

     case WM_PAINT:
          hdc = BeginPaint (hwnd, &ps) ;
          
          GetClientRect (hwnd, &rect) ;
          
          DrawText (hdc, TEXT ("Hello, Windows 98!"), -1, &rect,
                    DT_SINGLELINE | DT_CENTER | DT_VCENTER) ;
          EndPaint (hwnd, &ps) ;
          return 0 ;
          
     case WM_DESTROY:
          PostQuitMessage (0) ;
          return 0 ;
     }
     return DefWindowProc (hwnd, message, wParam, lParam) ;
}

Windows 函数

HWND WINAPI CreateWindow(
  _In_opt_ LPCTSTR   lpClassName,
  _In_opt_ LPCTSTR   lpWindowName,
  _In_     DWORD     dwStyle,            // Window Style
  _In_     int       x,
  _In_     int       y,
  _In_     int       nWidth,
  _In_     int       nHeight,
  _In_opt_ HWND      hWndParent,
  _In_opt_ HMENU     hMenu,
  _In_opt_ HINSTANCE hInstance,
  _In_opt_ LPVOID    lpParam
);

 1 //使用CreateWindow之前要先依次 【定义】和 【注册】  【窗口类型】
 2 //  【定义】 并初始化
 3 WNDCLASS wndclass;
 4 ......
 5 wndclass.lpszClassName = TEXT("WindowClassName"); 
 6 ......
 7 
 8 //  【注册】
 9     if (!RegisterClass (&wndclass))
10     {
11             MessageBox (  NULL, TEXT ("This program requires Windows NT!"), szAppName, MB_ICONERROR) ;
12             return 0 ;
13     }
14 
15 //CreateWindow 与 窗口类型wndclass 的联系是通过 CreateWindow 第一个 参数建立起来的
16 // 如果要使用上面第3行定义的 wndclass 则使用时第一个参数如下：
17 
18 hwnd1 = CreateWindow( TEXT("WindowClassName"),  // window class name
19                            .
20                            .
21                            .
22               　　　　　　　　　　　　 NULL) ;      // creation parameters    
23 
24 //CreateWindow 后必须使用以下两函数才能  显示和刷新
25     ShowWindow (hwnd1, iCmdShow) ; 　　　　//设置特定的状态
26     UpdateWindow (hwnd1) ;                // 向procedure 发送 MS_PAINT