First Win32 App, 第一个Win32 GUI程序

#include <windows.h>

LONG WINAPI WndProc(HWND, UINT,WPARAM,LPARAM);	//回调原型

int WINAPI WinMain(      
				   HINSTANCE 
				   hInstance,
				   HINSTANCE 
				   hPrevInstance,
				   LPSTR 
				   lpCmdLine,
				   int 
				   nCmdShow
				   )
{

	WNDCLASS wc;
	HWND hwnd;
	MSG msg;

	//1.设计窗体
	wc.style = 0;
	wc.lpfnWndProc = (WNDPROC)WndProc;
	wc.cbClsExtra = 0;
	wc.cbWndExtra = 0;
	wc.hInstance = hInstance;
	wc.hIcon = LoadIcon(NULL,IDI_WINLOGO);
	wc.hCursor = LoadCursor(NULL,IDC_ARROW);
	//wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
	wc.hbrBackground = (HBRUSH)(COLOR_GRAYTEXT);
	
	wc.lpszMenuName = NULL;
	wc.lpszClassName = "MyWndClass";

	RegisterClass(&wc);		//2.注册窗体

	hwnd = CreateWindow(	//3.创建窗体
			"MyWndClass",			//WNDCLASS NAME
			"SDK APPLICATION标题",		//WINDOW TITLE
			WS_OVERLAPPEDWINDOW,	//WINDOW STYLE
			CW_USEDEFAULT,			//Horizontal position
			CW_USEDEFAULT,			//Vertical position
			CW_USEDEFAULT,			//Initial width
			CW_USEDEFAULT,			//Initial height
			HWND_DESKTOP,			//Handle of parent window
			NULL,					//Menu handle
			hInstance,				//Application's instance handle
			NULL					//Window-creation data
		);


	ShowWindow(hwnd,nCmdShow);	//4.显示更新窗体
	UpdateWindow(hwnd);

	while(GetMessage(&msg,NULL,0,0)){		//5.消息循环
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}
	return msg.wParam;
}


LRESULT CALLBACK WndProc(HWND hwnd, UINT message,WPARAM wParam,LPARAM lParam){
	
	PAINTSTRUCT ps;
	HDC hdc;
	switch(message){
	case WM_PAINT:
		hdc=BeginPaint(hwnd,&ps);
		Ellipse(hdc,0,0,200,100);
		EndPaint(hwnd,&ps);
		return 0;
		
	case WM_DESTROY:
		PostQuitMessage(0);
		return 0;
	}
	return DefWindowProc(hwnd,message,wParam,lParam);
}