VC++深入详解-第一章学习心得(二)

前面介绍到了注册窗口，接下来进行窗口的创建，利用CreateWindow函数，结构如下

CreateWindowExW(
    DWORD dwExStyle,
    LPCWSTR lpClassName,	//指定窗口类的名称
    LPCWSTR lpWindowName,	//窗口名字
    DWORD dwStyle,		//窗口的样式 WS_xxx
    int X,		//x坐标
    int Y,		//y坐标
    int nWidth,		//宽度
    int nHeight,		//高度
    HWND hWndParent ,	//父窗口句柄
    HMENU hMenu,		//窗口菜单句柄
    HINSTANCE hInstance,	//窗口实例句柄
    LPVOID lpParam);	//大都设置为NULL
#ifdef UNICODE
#define CreateWindowEx  CreateWindowExW
#else
#define CreateWindowEx  CreateWindowExA
#endif // !UNICODE

窗口创建完成。接下来显示和更新窗口，结构分别如下

ShowWindow(
    HWND hWnd,	//创建窗口成功后返回的窗口句柄
    int nCmdShow);//窗口显示的状态SW_XXXX

UpdateWindow(
    HWND hWnd);	//创建窗口成功后返回的窗口句柄

接下来就是消息循环了。getMessage函数，结构如下

GetMessageW(
    LPMSG lpMsg,		//指向MSG消息结构体
    HWND hWnd ,		//指向窗口句柄，NULL代表接受所有的窗口信息
    UINT wMsgFilterMin,	//0
    UINT wMsgFilterMax);	//0
#ifdef UNICODE
#define GetMessage  GetMessageW
#else
#define GetMessage  GetMessageA
#endif // !UNICODE

使用方法如下：

	MSG msg;
	while (GetMessage(&msg,NULL,0,0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

接下来就是前面所提到的窗口过程函数，如下

LRESULT CALLBACK WinSunProc( HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam ); //窗口句柄，消息，两个附加信息

说了这么多，总结一下，窗口创建过程，就这几步骤

1.WinMain函数定义

2.设计一个窗口类

3.注册窗口类

4.创建窗口类

5.显示及更新窗口

6.进行消息寻环

7.编写窗口过程函数

下面贴上完整的代码：

#include <windows.h>
#include <stdio.h>

LRESULT CALLBACK WinSunProc( HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam );

int WINAPI WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd ){
	//设计一个窗口类
	WNDCLASS wndcls;
	wndcls.cbClsExtra = 0;
	wndcls.cbWndExtra = 0;
	wndcls.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);
	wndcls.hIcon = LoadIcon(NULL,IDI_ERROR);
	wndcls.hCursor = LoadCursor(NULL,IDC_CROSS);
	wndcls.hInstance = hInstance; //用用程序实例句柄由WinMain函数传过来
	wndcls.lpfnWndProc = WinSunProc;
	wndcls.lpszClassName = "刘凯";
	wndcls.lpszMenuName = NULL;
	wndcls.style = CS_HREDRAW | CS_VREDRAW;
	RegisterClass(&wndcls);

	//创建窗口，定义一个变量用来保存成功创建窗口后返回的句柄
	HWND hwnd;
	hwnd = CreateWindow("刘凯","第一个窗体",
			WS_OVERLAPPEDWINDOW,0,0,600,400,NULL,NULL,hInstance,NULL);

	//显示及刷新窗口
	ShowWindow(hwnd,SW_SHOWNORMAL);
	UpdateWindow(hwnd);

	//定义消息结构体，开始循环
	MSG msg;
	while (GetMessage(&msg,NULL,0,0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}
	return msg.wParam;
}

//编写窗口过程函数
LRESULT CALLBACK WinSunProc(
	HWND hwnd,
	UINT uMsg,
	WPARAM wParam,
	LPARAM lParam
	){
	switch (uMsg)
	{
	case  WM_CHAR :
		char szChar[20];
		sprintf(szChar,"char code is %d",wParam);
		MessageBox(hwnd,szChar,"char",0);
		break;
	case  WM_LBUTTONDBLCLK :
		MessageBox(hwnd,"mouse clicked","message",0);
		HDC hdc;
		hdc = GetDC(hwnd); //不能在相应WM_PAINT消息时调用
		TextOut(hdc,0,50,"程序之家",strlen("程序之家"));
		break;
	case WM_PAINT :
		HDC hDC;
		PAINTSTRUCT ps;
		hDC = BeginPaint(hwnd,&ps); //BeginPaint只能在响应WM_PAINT消息时调用
		TextOut(hDC,0,0,"http://www.baidu.com",strlen("http://www.baidu.com"));
		EndPaint(hwnd,&ps);
		break;

	case WM_CLOSE :
		if (IDYES == MessageBox(hwnd,"是否真的结束?","message",MB_YESNO))
		{
			DestroyWindow(hwnd);
		}
		break;
	case WM_DESTROY :
		PostQuitMessage(0);
		break;
	default:
		return DefWindowProc(hwnd,uMsg,wParam,lParam);

	}
	return 0;
}