使用dc画笔画矩形、直线与椭圆示例

/*简单的使用dc画笔画出直线，矩形，椭圆*/
#include<Windows.h>
#include<tchar.h>
//声明窗口函数
LRESULT CALLBACK WindowProc (
HWND hwnd,
UINT uMsg,
WPARAM wParam,
LPARAM lParam
);
//入口函数WinMain
int WINAPI WinMain(
HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow
)
{
//定义窗口类
WNDCLASS wndclass;
wndclass.lpfnWndProc=WindowProc;//指定窗口函数
wndclass.cbClsExtra=0;
wndclass.cbWndExtra=0;
wndclass.style=CS_HREDRAW|CS_VREDRAW;
wndclass.lpszClassName=_T("我的窗体");
wndclass.hInstance=hInstance;
wndclass.hCursor=LoadCursor(NULL,IDC_ARROW);//获取标准鼠标光标
wndclass.hIcon=0;
wndclass.hbrBackground=(HBRUSH)(COLOR_WINDOW+1);
wndclass.lpszMenuName=0;
//注册窗口类
if(RegisterClass(&wndclass)==0)
{
MessageBox(0,_T("注册窗口类失败"),_T("我的窗体"),MB_OK);
return 0;
}
//创建窗体实列
HWND hWnd = CreateWindow(_T("我的窗体"),_T("窗体绘图"),WS_OVERLAPPEDWINDOW,100,100,500,400,0,0,hInstance,0);
//显示和更新窗体
ShowWindow(hWnd,SW_SHOW);
UpdateWindow(hWnd);
//消息循环
MSG msg;
while(GetMessage(&msg,0,0,0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return 0;
}
//定义窗口函数
LRESULT CALLBACK WindowProc (
HWND hwnd,
UINT uMsg,
WPARAM wParam,
LPARAM lParam
)
{
switch(uMsg)
{
case WM_PAINT://响应绘图消息
{
PAINTSTRUCT ps;
//获得DC
HDC hDC = BeginPaint(hwnd,&ps);
//创建实线，宽度为1，红色的笔
HPEN hPen=CreatePen(PS_SOLID,1,RGB(255,0,0));
//将笔选入DC
HPEN hOldPen=(HPEN)SelectObject(hDC,hPen);
//绘制红色的直线
MoveToEx(hDC,10,10,NULL);
LineTo(hDC,90,50);
//创建一个蓝色的刷子
HBRUSH hBrush = CreateSolidBrush(RGB(0,0,255));
HBRUSH hOldBrush= (HBRUSH)SelectObject(hDC,hBrush);
//绘制矩形，因为笔没有换，所以绘制的是红色边框，蓝色区域的矩形
Rectangle(hDC,100,100,200,170);
//绘制椭圆，因为笔和刷子都没换，所以绘制的是红色的边框，蓝色区域的椭圆
Ellipse(hDC,200,230,260,300);
//输出文字
TextOut(hDC,200,30,_T("绘图测试"),4);
//恢复绘图对象
SelectObject(hDC,hOldPen);
SelectObject(hDC,hOldBrush);
//删除绘图对象
DeleteObject(hPen);
DeleteObject(hBrush);
//释放DC
EndPaint(hwnd,&ps);

}
break;
case WM_CLOSE:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hwnd,uMsg,wParam,lParam);
}
return 0;
}