C#实现拖动CogRecordDisplay中的CogPointMarker改变位置

private CogPointMarker mMarker;
private bool mIsDragging;
private CogRecordDisplay display;

// 读取图片
            CogImage8Grey image = new CogImage8Grey(new Bitmap(@"C:\Users\Administrator\Desktop\a.png"));

            // 创建marker对象
            mMarker = new CogPointMarker();
            mMarker.LineWidthInScreenPixels = 5;
            mMarker.X = 100;
            mMarker.Y = 100;
            mMarker.Color = CogColorConstants.Red;
           
            // 显示结果
             display = new CogRecordDisplay();
            display.Dock = DockStyle.Fill;
            this.Controls.Add(display);
            display.Image = image;
            display.Fit(true);

           
            // 在CogDisplay控件上显示marker对象
            display.InteractiveGraphics.Add(mMarker, "point", false);
         
       
            // 注册鼠标事件
            display.MouseDown += new MouseEventHandler(mCogDisplay_MouseDown);
            display.MouseMove += new MouseEventHandler(mCogDisplay_MouseMove);
            display.MouseUp += new MouseEventHandler(mCogDisplay_MouseUp);