我的第一个完整的Windows应用程序

#include<windows.h>
LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);
int WINAPI WinMain (HINSTANCE hInstance,HINSTANCE hPrevInstance,
					LPSTR lpCmdLine,int nCmdShow)
{
	HWND	hwnd;
	MSG		msg;
	WNDCLASS wndclass;
	wndclass.style =CS_HREDRAW|CS_VREDRAW;
	wndclass.lpfnWndProc =WndProc;
	wndclass.cbClsExtra =0;
	wndclass.cbWndExtra =0;
	wndclass.hInstance =0;
	wndclass.hIcon		=LoadIcon(NULL,IDI_APPLICATION);
	wndclass.hCursor	=LoadCursor(NULL,IDC_ARROW);
	wndclass.hbrBackground	=(HBRUSH)GetStockObject(WHITE_BRUSH);
	wndclass.lpszMenuName   =NULL;
	wndclass.lpszClassName	="HelloWin";
	if(!RegisterClass(&wndclass))
	{
		MessageBox(NULL,"窗口注册失败！","HelloWin",0);
		return 0;
	}
	hwnd=CreateWindow("HelloWin",
		"啊！C++",
		WS_OVERLAPPEDWINDOW,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		NULL,
		NULL,
		hInstance,
		NULL);
	ShowWindow(hwnd,nCmdShow);
	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)
{
	switch(message)
	{
	case WM_CREATE:
			return 0;
	case WM_LBUTTONDOWN:
			MessageBox(NULL,"春天在哪里啊 春天在哪里~~~~~","我的春天来了",0);
			return 0;
	case WM_DESTROY:
		    PostQuitMessage(0);
			return 0;
	}
	return DefWindowProc(hwnd,message,wParam,lParam);
}