C#使用NPOI設置Excel下拉選項

public static void SetCellDropdownList(ISheet sheet, int firstcol, int lastcol, string[] vals)
{
     //設置生成下拉框的行和列
     var cellRegions = new CellRangeAddressList(1, 65535, firstcol, lastcol);
 
     //設置 下拉框內容
     DVConstraint constraint = DVConstraint.CreateExplicitListConstraint(vals);
 
     //綁定下拉框和作用區域，並設置錯誤提示信息
     HSSFDataValidation dataValidate = new HSSFDataValidation(cellRegions, constraint);
     dataValidate.CreateErrorBox("輸入不合法", "請輸入或選擇下拉列表中的值。");
     dataValidate.ShowPromptBox = true;
 
     sheet.AddValidationData(dataValidate);
}

HSSFWorkbook workbook = new HSSFWorkbook();
ISheet sheet = workbook.CreateSheet("sheet1");
ExcelHelper.SetCellDropdownList(sheet, 1, 1, new List<string>() { "男", "女", "保密" }.ToArray());

public static void SetCellDropdownList(HSSFWorkbook workbook, ISheet sheet, string name, int firstcol, int lastcol, string[] vals, int sheetindex = 1)
{
      //先創建一個Sheet專門用於存儲下拉項的值
      ISheet sheet2 = workbook.CreateSheet(name);
      //隱藏
      workbook.SetSheetHidden(sheetindex, true);
      int index = 0;
      foreach (var item in vals)
      {
          sheet2.CreateRow(index).CreateCell(0).SetCellValue(item);
          index++;
      }
      //創建的下拉項的區域：
      var rangeName = name + "Range";
      IName range = workbook.CreateName();
      range.RefersToFormula = name + "!$A$1:$A$" + index;
      range.NameName = rangeName;
      CellRangeAddressList regions = new CellRangeAddressList(0, 65535, firstcol, lastcol);
 
      DVConstraint constraint = DVConstraint.CreateFormulaListConstraint(rangeName);
      HSSFDataValidation dataValidate = new HSSFDataValidation(regions, constraint);
      dataValidate.CreateErrorBox("輸入不合法", "請輸入或選擇下拉列表中的值。");
      dataValidate.ShowPromptBox = true;
      sheet.AddValidationData(dataValidate);
}

HSSFWorkbook workbook = new HSSFWorkbook();
ISheet sheet = workbook.CreateSheet("sheet1");
var roomTypeList = GetRoomTypeNameList();
ExcelHelper.SetCellDropdownList(workbook, sheet, "RoomTypeDictionary", 1, 1, roomTypeList.ToArray());

private void SetCityCellDropdownList(HSSFWorkbook workbook, ISheet sheet, string dictionaryName, int citycol, int areacol, int sheetIndex)
{
    var citylist = GetCityList();
    int citycount = citylist.Count;
    ISheet sheet2 = workbook.CreateSheet(dictionaryName);
    //隱藏
    workbook.SetSheetHidden(sheetIndex, true);
 
    #region 城市區域數據構造
    //城市
    int rowIndex = 0;
    foreach (var item in citylist)
    {
        IRow row = sheet2.CreateRow(rowIndex);
        row.CreateCell(0).SetCellValue(item.Name);
 
        rowIndex++;
    }
    //區域
    int n_rowIndex = 0;
    foreach (var item in citylist)
    {
        int areaIndex = 0;
        foreach (var area in item.AreaList)
        {
            IRow row = sheet2.GetRow(areaIndex);
            if (row == null)
            {
                row = sheet2.CreateRow(areaIndex);
            }
            row.CreateCell(n_rowIndex + 1).SetCellValue(area.Name);
            areaIndex++;
        }
        n_rowIndex++;
    }
    #endregion
 
    #region 設置數據字段范圍
    //定義城市
    int columnIndex = 1;
    IName range_Country = workbook.CreateName();
    range_Country.RefersToFormula = string.Format("{0}!${1}$1:${1}${2}", dictionaryName, GetExcelColumnName(columnIndex), citycount);
    range_Country.NameName = "城市";
 
    //定義區
    foreach (var item in citylist)
    {
        int areacount = item.AreaList.Count;
        columnIndex++;
        IName range_area = workbook.CreateName();
        range_area.RefersToFormula = string.Format("{0}!${1}$1:${1}${2}", dictionaryName, GetExcelColumnName(columnIndex), areacount);
        range_area.NameName = item.Name;
    }
 
    //城市列表下拉綁定
    ExcelHelper.SetCellDropdownList(sheet, 1, 65535, citycol, citycol, "城市");
 
    //第二列，跟隨第一列聯動
    string colName = GetExcelColumnName(areacol);
    for (int j = 1; j < 500; j++)
    {
        ExcelHelper.SetCellDropdownList(sheet, j, j, areacol, areacol, string.Format("INDIRECT(${0}${1})", colName, j + 1));
    }
    #endregion
}
 
private string GetExcelColumnName(int columnNumber)
{
    int dividend = columnNumber;
    string columnName = String.Empty;
    int modulo;
 
    while (dividend > 0)
    {
        modulo = (dividend - 1) % 26;
        columnName = Convert.ToChar(65 + modulo).ToString() + columnName;
        dividend = (int)((dividend - modulo) / 26);
    }
 
    return columnName;
}

public static void SetCellDropdownList(ISheet sheet, int firstRow, int lastRow, int firstCol, int lastCol, string name)
{
    CellRangeAddressList regions = new CellRangeAddressList(firstRow, lastRow, firstCol, lastCol);
    DVConstraint constraint = DVConstraint.CreateFormulaListConstraint(name);
    HSSFDataValidation dataValidate = new HSSFDataValidation(regions, constraint);
    dataValidate.CreateErrorBox("輸入不合法", "請輸入或選擇下拉列表中的值。");
    sheet.AddValidationData(dataValidate);
}

HSSFWorkbook workbook = new HSSFWorkbook();
ISheet sheet = workbook.CreateSheet("sheet1");
SetCityCellDropdownList(workbook, sheet, "CityDictionary", 1, 2, 1);