code: function (cell) {
              if (!cell) return;
              var cellIndex = cell.cellIndex,
                  rowIndex = cell.parentNode.rowIndex,
                  rowInfo = this.indexTable[rowIndex],
                  numCols = this.colsNum;
              for (var colIndex = cellIndex; colIndex < numCols; colIndex++) {
                  var cellInfo = rowInfo[colIndex];
                  if (cellInfo.rowIndex === rowIndex && cellInfo.cellIndex === cellIndex) {
                      return cellInfo;
                  }
              }
          }
docs: 获取单元格的索引信息