/// <summary>
 /// 添加文字
 /// </summary>
 /// <param name="pos">添加的位置</param>
 /// <param name="obj">添加的对象</param>
 public void Insert(int pos, EditorContent obj)
 {
     ContentHandleContext content = new ContentHandleContext();
     content.Input(this,pos, obj);
     this.SortContent();
 }
 /// <summary>
 /// 绘制选择区域的背景色
 /// </summary>
 /// <param name="draw">用来绘制图像的设备</param>
 /// <param name="content">内容</param>
 /// <param name="color">背景颜色</param>
 private void DrawBackground(IDraw draw,EditorContent content,int color)
 {
     draw.FillRectangle(
                 color,
                 content.Rectangle.Left,
                 content.Rectangle.Top,
                 content.Rectangle.Width,
                 content.Rectangle.Height,
                 null);
 }
 /// <summary>
 /// 添加编辑内容对象
 /// </summary>
 /// <param name="obj"></param>
 public void Add(EditorContent obj)
 {
     this.Insert(this.SelectIndex, obj);
 }