private Integer dataLength(List<WriteCellData<?>> cellDataList, Cell cell, Boolean isHead) {
        if (isHead) {
            return cell.getStringCellValue().getBytes().length;
        }
        WriteCellData<?> cellData = cellDataList.get(0);
        CellDataTypeEnum type = cellData.getType();
        if (type == null) {
            return -1;
        }
        switch (type) {
            case STRING:
                return cellData.getStringValue().getBytes().length;
            case BOOLEAN:
                return cellData.getBooleanValue().toString().getBytes().length;
            case NUMBER:
                return cellData.getNumberValue().toString().getBytes().length;
            default:
                return -1;
        }
    }
Take the width of the longest column as the width.
<p>
This is not very useful at the moment, for example if you have Numbers it will cause a newline.And the length is not
exactly the same as the actual length.

@author Jiaju Zhuang
fastexcel-core/src/main/java/cn/idev/excel/write/style/column/LongestMatchColumnWidthStyleStrategy.java