VS2010 win32项目windows窗体程序 向导生成代码解析

目录：

1.Win32项目的windows窗体程序的向导生成了如下代码

2.手工生成代码如下

3.当消息队列中没有消息需要处理，我们可以利用这段时间处理我们自己的任务

1.Win32项目的windows窗体程序的向导生成了如下代码：

// Timer.cpp : 定义应用程序的入口点。//#include "stdafx.h"#include "Timer.h"#define MAX_LOADSTRING 100// 全局变量:HINSTANCE hInst;// 当前实例TCHAR szTitle[MAX_LOADSTRING];// 标题栏文本TCHAR szWindowClass[MAX_LOADSTRING];// 主窗口类名// 此代码模块中包含的函数的前向声明:ATOMMyRegisterClass(HINSTANCE hInstance);BOOLInitInstance(HINSTANCE, int);LRESULT CALLBACKWndProc(HWND, UINT, WPARAM, LPARAM);INT_PTR CALLBACKAbout(HWND, UINT, WPARAM, LPARAM);int APIENTRY _tWinMain(HINSTANCE hInstance,                     HINSTANCE hPrevInstance,                     LPTSTR    lpCmdLine,                     int       nCmdShow){UNREFERENCED_PARAMETER(hPrevInstance);UNREFERENCED_PARAMETER(lpCmdLine); // TODO: 在此放置代码。MSG msg;HACCEL hAccelTable;// 初始化全局字符串LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);   ///加载标题栏字符串LoadString(hInstance, IDC_TIMER, szWindowClass, MAX_LOADSTRING);  ///加载“关于对话框”MyRegisterClass(hInstance);// 执行应用程序初始化:if (!InitInstance (hInstance, nCmdShow)){return FALSE;}/*函数原型：int TranslateAccelerator（HWND hWnd,HACCEL hAccTable，LPMSG IpMsg）;       函数功能：翻译加速键表。该函数处理菜单命令中的加速键。该函数将一个WM_KEYDOWN或WM_SYSKEYDOWN消息翻译成一个WM_COMMAND或WM_SYSCOMMAND消息（如果在给定的加速键表中有该键的入口），然后将WM_COMMAND或WM_SYSCOMMAND消息直接送到相应的窗口处理过程。       TranslateAccelerator直到窗口过程处理完消息后才返回。参数：hWnd:窗口句柄，该窗口的消息将被翻译。hAccTable:加速键表句柄。加速键表必须由LoadAccelerators函数调用装入或由CreateAccd_eratorTable函数调用创建。LpMsg:MSG结构指针，MSG结构中包含了从使用GetMessage或PeekMessage函数调用线程消息队列中得到的消息内容。返回值：若函数调用成功，则返回非零值；若函数调用失败，则返回值为零。若要获得更多的错误信息，可调用GetLastError函数。*/hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_TIMER));// 主消息循环:while (GetMessage(&msg, NULL, 0, 0)){if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg)){TranslateMessage(&msg);DispatchMessage(&msg);}}return (int) msg.wParam;}////  函数: MyRegisterClass()////  目的: 注册窗口类。////  注释:////    仅当希望//    此代码与添加到 Windows 95 中的“RegisterClassEx”//    函数之前的 Win32 系统兼容时，才需要此函数及其用法。调用此函数十分重要，//    这样应用程序就可以获得关联的//    “格式正确的”小图标。//ATOM MyRegisterClass(HINSTANCE hInstance){WNDCLASSEX wcex;wcex.cbSize = sizeof(WNDCLASSEX);   ///注册类对象的大小wcex.style= CS_HREDRAW | CS_VREDRAW;   ///注册类的风格wcex.lpfnWndProc= WndProc;   ///消息处理函数wcex.cbClsExtra= 0;wcex.cbWndExtra= 0;wcex.hInstance= hInstance;  ///应用程序实例句柄，系统提供的wcex.hIcon= LoadIcon(hInstance, MAKEINTRESOURCE(IDI_TIMER));   ///图标wcex.hCursor= LoadCursor(NULL, IDC_ARROW);   ///光标wcex.hbrBackground= (HBRUSH)(COLOR_WINDOW+1);   ///背景画刷设定wcex.lpszMenuName= /*MAKEINTRESOURCE(IDC_TIMER)*/NULL;      ///菜单wcex.lpszClassName= szWindowClass;    //注册类wcex.hIconSm= LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL));  ///小图标return RegisterClassEx(&wcex);}////   函数: InitInstance(HINSTANCE, int)////   目的: 保存实例句柄并创建主窗口////   注释:////        在此函数中，我们在全局变量中保存实例句柄并//        创建和显示主程序窗口。//BOOL InitInstance(HINSTANCE hInstance, int nCmdShow){   HWND hWnd;   hInst = hInstance; // 将实例句柄存储在全局变量中   hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);   if (!hWnd)   {      return FALSE;   }   ///MoveWindow(hWnd,100,100,640,320,true);   ShowWindow(hWnd, nCmdShow);   UpdateWindow(hWnd);   return TRUE;}////  函数: WndProc(HWND, UINT, WPARAM, LPARAM)////  目的: 处理主窗口的消息。////  WM_COMMAND- 处理应用程序菜单//  WM_PAINT- 绘制主窗口//  WM_DESTROY- 发送退出消息并返回////LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){int wmId, wmEvent;PAINTSTRUCT ps;HDC hdc;switch (message){case WM_COMMAND:wmId    = LOWORD(wParam);wmEvent = HIWORD(wParam);// 分析菜单选择:switch (wmId){case IDM_ABOUT:DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About);break;case IDM_EXIT:DestroyWindow(hWnd);break;default:return DefWindowProc(hWnd, message, wParam, lParam);}break;case WM_PAINT:hdc = BeginPaint(hWnd, &ps);// TODO: 在此添加任意绘图代码...EndPaint(hWnd, &ps);break;case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProc(hWnd, message, wParam, lParam);}return 0;}// “关于”框的消息处理程序。INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam){UNREFERENCED_PARAMETER(lParam);switch (message){case WM_INITDIALOG:return (INT_PTR)TRUE;case WM_COMMAND:if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL){EndDialog(hDlg, LOWORD(wParam));return (INT_PTR)TRUE;}break;}return (INT_PTR)FALSE;}

2.手工生成代码如下：

#include <windows.h>void MyPaint(HDC hdc, LPARAM lParam ){   //绘图代码}//我的消息过程处理函数LRESULT CALLBACK WndProc( HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam){PAINTSTRUCT ps;HDC hdc;switch (message){case WM_PAINT:hdc = BeginPaint(hWnd, &ps);EndPaint(hWnd,&ps);break;case WM_MOUSEMOVE:hdc = GetDC(hWnd);MyPaint(hdc,lParam);ReleaseDC(hWnd,hdc);break;    case WM_DESTROY:PostQuitMessage(0);break;default:return DefWindowProc(hWnd, message,wParam,lParam);}return 0;}//初始化实例函数BOOL InistInstance( HINSTANCE hInstance, int nCmdShow){HWND hWnd;hWnd = CreateWindow("canvas","绘图窗口",WS_OVERLAPPEDWINDOW, 350,110,CW_USEDEFAULT,50,NULL,NULL,hInstance,NULL);if ( !hWnd ){return FALSE;}MoveWindow( hWnd,350,110,450,250,true);ShowWindow( hWnd, nCmdShow);UpdateWindow( hWnd);return TRUE;}//我的窗口注册函数ATOM MyRegisterClass(HINSTANCE hInstance){WNDCLASSEX wcex;wcex.cbSize = sizeof(WNDCLASSEX);wcex.style = CS_HREDRAW | CS_VREDRAW;wcex.lpfnWndProc = (WNDPROC)WndProc;wcex.cbClsExtra = 0;wcex.cbWndExtra = 0;wcex.hInstance = hInstance;wcex.hIcon = NULL;wcex.hCursor = LoadCursor(NULL,IDC_ARROW);wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1 );wcex.lpszMenuName = NULL;wcex.lpszClassName = "canvas";wcex.hIconSm = NULL;return RegisterClassEx(&wcex);}//程序入口函数int APIENTRY WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow ){MSG msg;MyRegisterClass(hInstance);if ( !InistInstance(hInstance,nCmdShow)){return FALSE;}while ( GetMessage( &msg, NULL, 0, 0) ){TranslateMessage(&msg);DispatchMessage(&msg);}return msg.wParam;}

3.当消息队列中没有消息需要处理，我们可以利用这段时间处理我们自己的任务：

// 消息循环MSG msg;ZeroMemory(&msg, sizeof(msg));   //这句特别重要，因为需要将msg初始化后才不会引起编译异常、运行异常while (msg.message!=WM_QUIT){if (PeekMessage(&msg, NULL, 0U, 0U, PM_REMOVE)){TranslateMessage(&msg);DispatchMessage(&msg);}else{Direct3DRender();       // 绘制3D场景}}