Windows消息运行机制

 Windows内部运行机制，一直是有个大略的了解，主要是了解了这几个方面：

一、Windows窗口的设计、注册、创建、显示更新；

二、消息循环；了解windows消息的基本情况，还是要把代码敲一下，有个初步的肌肤之亲。

 

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

LRESULT CALLBACK WinTianProc(HWND hwnd, UINT uMsg, WPARAM wparam, LPARAM lparam);

int WINAPI WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd )
{
	
	WNDCLASS wndclass;
	wndclass.cbClsExtra = 0;
	wndclass.cbWndExtra = 0;
	wndclass.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);
	wndclass.hCursor = LoadCursor(NULL,IDC_CROSS);
	wndclass.hIcon = LoadIcon(NULL,IDI_ERROR);
	wndclass.hInstance = hInstance;
	wndclass.lpfnWndProc = WinTianProc;
	wndclass.lpszClassName = "tian";
	wndclass.lpszMenuName = NULL;
	wndclass.style = CS_HREDRAW | CS_VREDRAW;

	RegisterClass(&wndclass);

	HWND hwnd;
	hwnd = CreateWindow("tian","abc",WS_OVERLAPPEDWINDOW,0,0,600,400,NULL,NULL,hInstance,NULL);

	ShowWindow(hwnd,SW_SHOWNORMAL);
	UpdateWindow(hwnd);

	BOOL bRet;
	MSG msg;
	while(bRet = GetMessage(&msg,NULL,0,0))
	{
		if (-1 == bRet)
		{
			break;
		}
		else
		{
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
	
	}

	return msg.wParam;
}

LRESULT CALLBACK WinTianProc(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_LBUTTONDOWN:
		MessageBox(hwnd,"mouse clicked","message",0);
		HDC hdc;
		hdc = GetDC(hwnd);
		TextOut(hdc,0,9,"程序员之家",strlen("程序员之家"));
		break;

	case WM_PAINT:
		HDC hDC;
		PAINTSTRUCT ps;
		hDC = BeginPaint(hwnd,&ps);
		TextOut(hDC,0,50,"abc",strlen("abc"));
		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;
}