win32。创建窗口类，注册窗口类，创建窗口，刷新窗口。但是窗口没法显示？！

2018-10-04 01:57:55 307 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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在C 语言 Win32API中实现窗口的步骤窗口类可视为窗口的详细蓝图，它全方位地定义了窗口的外观、行为以及处理各类消息的方式。在 C 语言中，我们通过定义一个WNDCLASS结构体来塑造窗口类。：这一成员指向窗口过程函数，它堪称窗口的 “大脑”。当用户进行鼠标点击、键盘敲击、调整窗口大小等操作时，系统会向窗口发送相应消息，而此函数负责解读并响应这些消息，决定窗口该如何应对。hInstance：应用程序实例句柄，从WinMain函数的参数中获取。阅读详情



#include <Windows.h>

#include <stdio.h>



LRESULT CALLBACK WinSunProc(

	HWND hwnd,       /*窗口句柄*/

	UINT uMsg,       /*信息标识*/

	WPARAM wParam,

	LPARAM lParam

);



int WINAPI WinMain(

	HINSTANCE hInstance,       /*当前实例句柄*/

	HINSTANCE hPrevInstance,   /*上一个实例句柄*/

	LPSTR lpCmdLine,           /*命令行*/

	int nCmdShow               /*显示状态*/

)

{

	/*设计一个窗口类*/

	WNDCLASS wndcle;

	wndcle.cbClsExtra = 0;

	wndcle.cbWndExtra = 0;

	wndcle.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);

	wndcle.hCursor = LoadCursor(NULL, IDC_CROSS);

	wndcle.hIcon = LoadIcon(NULL, IDI_ERROR);

	wndcle.hInstance = hInstance;

	wndcle.lpfnWndProc = WinSunProc;

	wndcle.lpszClassName = TEXT("lpl2018");

	wndcle.lpszMenuName = NULL;

	wndcle.style = CS_HREDRAW | CS_VREDRAW;



	RegisterClass(&wndcle);





	char pszErrMsg[128] = { 0 };



	/*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(TEXT("LCK2018"), TEXT("http://www.baidu.com"), WS_OVERLAPPEDWINDOW, 0, 0, 600, 400, NULL, NULL, hInstance, NULL);

	if (hwnd == NULL) {

		snprintf(pszErrMsg,sizeof(pszErrMsg),TEXT("err[%d]"), GetLastError());

		OutputDebugString(pszErrMsg);

		MessageBox(NULL, "CreateWindow Err", "Error", 0);

	}

	

	/*显示及刷新窗口*/

	ShowWindow(hwnd, SW_SHOWNORMAL);

	UpdateWindow(hwnd);



	/*定义消息结构体,开始消息循环*/

	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,       /*窗口句柄*/

	UINT uMsg,       /*信息标识*/

	WPARAM wParam,

	LPARAM lParam

)

{



	switch (uMsg)

	{

	case WM_CHAR:

		char szChar[20];

		sprintf_s(szChar, "char code is %d", wParam);

		MessageBox(hwnd, szChar, TEXT("char"), 0);

		break;

	case WM_LBUTTONDOWN:

		MessageBox(hwnd, "mouse clicked", "message", 0);

		HDC hdc;

		hdc = GetDC(hwnd); /*不能再相应WM_PAINT 消息时调用*/

		TextOut(hdc, 0, 50, TEXT("LOL HOME"), strlen("LOL HOME"));

		/*ReleaseDC(hwnd,hdc);*/

		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.csdn.com", strlen("http://www.csdn.com"));

		EndPaint(hwnd, &ps);

		break;

	case WM_CLOSE:

		if (IDYES == MessageBox(hwnd, "Is End?", "message", MB_YESNO))

        {

			DestroyWindow(hwnd);

        }

	case WM_DESTROY:

		PostQuitMessage(0);

		break;

	default:

		return DefWindowProc(hwnd, uMsg, wParam, lParam);

	}



	return 0;

}