VC画线代码：MoveToEx/LineTo

LRESULT paint(HWND hWnd, HDC hDC)
{
    HPEN hPen;

    RECT clientDimension;       //存放客户区的尺寸
    POINT begin; //保存点的信息，org表示圆心坐标

    GetClientRect(hWnd,&clientDimension);   //获取客户区的尺寸
    if((clientDimension.right-clientDimension.left)<400|| (clientDimension.bottom-clientDimension.top)<300) //判断屏幕尺寸
    {
        MessageBox(hWnd,L"屏幕尺寸太小，无法绘图！",L"错误信息",0);
        return 0;
    }

    begin.x = 100;
    begin.y =  50;

    //先写字，再画线。否则线可能被字冲没了。
    TextOut(hDC,begin.x,begin.y, buffer, lstrlen(buffer));

    hPen=CreatePen(PS_SOLID,1,RGB(255,0,0));
    SelectObject(hDC,hPen); 

    int my = 100;
    int length = 300;
    MoveToEx(hDC, begin.x, my, NULL);
    LineTo(hDC, begin.x+length, my);

    my = 200;
    MoveToEx(hDC, begin.x, my, NULL);
    LineTo(hDC, begin.x+length, my);
}