鼠标(1)

鼠标的按钮操作，主要以下三种

1单击：然下鼠标，然后松开

2双击：连续两次快速按下鼠标按钮，然后松开

3保持按下按钮，并移动鼠标

下面看看按钮事件：

按钮	按下	释放	第二次按下按钮
左键	WM_LBUTTONDOWN	WM_LBUTTONUP	WM_LBUTTONDBLCLK
中键	WM_MBUTTONDOWN	WM_MBUTTONUP	WM_MBUTTONDBLCLK
右键	WM_RBUTTONDOWN	WM_RBUTTONUP	WM_RBUTTONDBLCLK

下面是一个简单的鼠标处理事例：

#include<windows.h>
#include<windowsx.h>//GET_X_LPARAM (lParam)此类函数在这个头文件里
#define MAXPOINTS 1000
LRESULT CALLBACK WindowProc(
  HWND hwnd,      // handle to window
  UINT uMsg,      // message identifier
  WPARAM wParam,  // first message parameter
  LPARAM lParam   // second message parameter
);

int WINAPI WinMain(
  HINSTANCE hInstance,      // handle to current instance
  HINSTANCE hPrevInstance,  // handle to previous instance
  LPSTR lpCmdLine,          // command line
  int nCmdShow              // show state
)
{
	static TCHAR szAppName[]=TEXT("leidemingzi");
	HWND hwnd;
	MSG msg;
	WNDCLASS wndclass;

	wndclass.cbClsExtra=0;
	wndclass.cbWndExtra=0;
	wndclass.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);
	wndclass.hCursor=LoadCursor(NULL,IDC_ARROW);
	wndclass.hIcon=LoadIcon(NULL,IDI_ERROR);
	wndclass.hInstance=hInstance;
	wndclass.lpfnWndProc=WindowProc;
	wndclass.lpszClassName=szAppName;
	wndclass.lpszMenuName=NULL;
	wndclass.style=CS_HREDRAW|CS_VREDRAW;

	if(!RegisterClass(&wndclass))
	{
		MessageBox(NULL,TEXT("the program require window NT"),szAppName,MB_ICONERROR);
		return 0;
	}

	hwnd=CreateWindow(
 szAppName,  // registered class name
  TEXT("this is title"), // window name
  WS_OVERLAPPEDWINDOW,        // window style
  CW_USEDEFAULT,                // horizontal position of window
  CW_USEDEFAULT,                // vertical position of window
  CW_USEDEFAULT,           // window width
  CW_USEDEFAULT,          // window height
  NULL,      // handle to parent or owner window
  NULL,          // menu handle or child identifier
  hInstance,  // handle to application instance
  NULL        // window-creation data
);

	ShowWindow(hwnd,nCmdShow);
	UpdateWindow(hwnd);

	while(GetMessage(&msg,NULL,0,0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}
	return msg.wParam;
}

LRESULT CALLBACK WindowProc(
  HWND hwnd,      // handle to window
  UINT uMsg,      // message identifier
  WPARAM wParam,  // first message parameter
  LPARAM lParam   // second message parameter
)
{
	HDC hdc;
	PAINTSTRUCT ps;
	static int iCount;
	static POINT pt[MAXPOINTS];
	int i,j;

	switch(uMsg)
	{
		case WM_LBUTTONDOWN:
			iCount=0;
			InvalidateRect(hwnd,NULL,TRUE);
			return 0;

		case WM_MOUSEMOVE:
		if(wParam & MK_LBUTTON & (iCount<1000))//很重要喔
		{
			 pt[iCount  ].x = GET_X_LPARAM (lParam) ;
              		 pt[iCount++].y = GET_Y_LPARAM (lParam) ;
               
            		   hdc = GetDC (hwnd) ;
              		 SetPixel (hdc, GET_X_LPARAM (lParam), GET_Y_LPARAM (lParam), 0) ;
              		 ReleaseDC (hwnd, hdc) ;
		}
		return 0;

		case WM_LBUTTONUP:
			InvalidateRect(hwnd,NULL,FALSE);//使矩形区域无效，触动WM_PAINT事件，并且WM_PAINT事件的时候，不删除原来的区域内容
			return 0;

		case WM_PAINT:
			hdc=BeginPaint(hwnd,&ps);
			SetCursor(LoadCursor(NULL,IDC_WAIT));//把鼠标设置为忙碌状态
			ShowCursor(TRUE);//显示鼠标

			 for (i = 0 ; i < iCount - 1 ; i++)
              			 for (j = i + 1 ; j < iCount ; j++)
            		   {
                   		 MoveToEx (hdc, pt[i].x, pt[i].y, NULL) ;//起点
                    		LineTo   (hdc, pt[j].x, pt[j].y) ;//画线
              		 }

			ShowCursor(FALSE);
			SetCursor(LoadCursor(NULL,IDC_ARROW));

			EndPaint(hwnd,&ps);
			return 0;
			
		case WM_DESTROY:
			PostQuitMessage(0);
			return 0;
		
	}
	return DefWindowProc(hwnd,uMsg,wParam,lParam);
}

其中的一个效果图如下：