NPOI，给指定的excle创建个下拉框验证

NPOI，给指定的excle创建个下拉框验证

先大致看下效果吧

 Nuget  搜索 NPOI，一般出来的第一个就是，安装NPOI基础环境

using NPOI.HSSF.UserModel;
using NPOI.OpenXmlFormats.Spreadsheet;
using NPOI.SS.UserModel;
using NPOI.SS.Util;
using NPOI.XSSF.UserModel;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Path = System.IO.Path;

namespace NPOIDemo
{
    /// 

    /// MainWindow.xaml 的交互逻辑
    /// 
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            var ff = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "服务器导入模板.xlsx");
            CreateCellDropDownList(
                ff,
                new string[] { "1111", "2222", "3333", "4444" },
                1, 4, 3, 3
                );
            System.Diagnostics.Process.Start(ff);
        }

        /// 

        /// 给指定的excle添加个下拉框验证
        /// 备注：只能给未添加下拉框验证的添加，追加的情况不理想
        /// 
        /// excle路径
        /// 有效值集合
        public void CreateCellDropDownList(string exclepath, string[] dropDownlist, int firstRow = 0, int lastRow = 65535, int firstCol = 0, int lastCol = 256)
        {
            FileInfo file = new FileInfo(exclepath);
            if (!file.Exists)
            {
                throw new FileNotFoundException("Excle文件不存在！");
            }
            if (dropDownlist == null || dropDownlist.Length == 0)
            {
                throw new ValueUnavailableException("有效值集合不允许为空！");
            }
            if (firstRow < 0 || lastRow < 0 || firstCol < 0 || lastCol < 0)
            {
                throw new IndexOutOfRangeException("索引值下标有误，从0开始！");
            }
            file.IsReadOnly = false;

            IWorkbook workbook = null;

            using (FileStream fs = File.Open(file.FullName, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
            {
                workbook = new XSSFWorkbook(fs);
            }

            ISheet sheet = workbook.GetSheetAt(0);

            //设置默认值

            for (int irow = firstRow, length = lastRow; irow <= length; irow++)
            {
                var row = sheet.GetRow(irow);
                if (row == null)
                {
                    continue;
                }

                for (int icell = firstCol, lengthc = lastCol; icell <= lengthc; icell++)
                {
                    var cell = row.GetCell(icell);
                    if (cell == null)
                    {
                        continue;
                    }
                    cell.SetCellValue(dropDownlist.First());
                }
            }

            //设置生成下拉框的行和列
            CellRangeAddressList cellRegions = new CellRangeAddressList(firstRow, lastRow, firstCol, lastCol);

            XSSFDataValidationHelper helper = new XSSFDataValidationHelper((XSSFSheet)sheet);
            //启用下拉验证
            var dropDownConstraint = helper.CreateExplicitListConstraint(dropDownlist);
            IDataValidation dropDownValidation = helper.CreateValidation(dropDownConstraint, cellRegions);
            sheet.AddValidationData(dropDownValidation);
            sheet.ValidateMergedRegions();

            var filenew = Path.Combine(file.DirectoryName, "filenew" + Path.GetExtension(file.Name));
            using (FileStream fs = File.Open(filenew, FileMode.OpenOrCreate, FileAccess.ReadWrite))
            {
                workbook.Write(fs);
            }

            //因为暂时无法解决编辑的情况，所以迂回下，删除原始再覆盖下
            File.Delete(file.FullName);
            File.Move(filenew, file.FullName);
        }
    }
}

特此说明下：添加下拉框数据验证在已经存在的情况不理想，后面生成的会失效，暂时没找到解决办法，只有每次生成的数据操作一个空数据验证的模板