docs: function rowDragFun(e) {
      var oThis = this;
      // 拖拽时动态生成图标
      if (!oThis.options.canRowDrag) {
          return;
      }
  
      if (this.rowDragFlag) {
          this.rowDragEndX = e.clientX;
          this.rowDragEndY = e.clientY;
          var changeX = this.rowDragEndX - this.rowDragStartX,
              changeY = this.rowDragEndY - this.rowDragStartY;
          var rowHeight = this.rowDragEle.clientHeight;
  
          var rowCounts = parseInt(changeY / rowHeight);
  
          if (rowCounts < 0) {
              this.dragdirection = -1;
          } else {
              this.dragdirection = 1;
          }
  
          this.rowDragEndIndex = this.rowDragStartIndex + rowCounts;
  
          if (this.rowDragEndIndex < 0) {
              this.rowDragEndIndex = 0;
          }
  
          if (this.rowDragEndIndex != this.rowDragStartIndex) {
              // var $flagIconDom = $('<span class="uf uf-moveoption" />');
              //先删除相关的标记元素
              $('#' + this.options.id + '_content_tbody').find('tr td').removeClass('u-grid-drag-icon');
              //添加标记元素
              $('#' + this.options.id + '_content_tbody').find('tr').eq(this.rowDragEndIndex).find('td').first().addClass('u-grid-drag-icon');
          }
      }
  }