使用Apache POI生成Excel下拉列表时的限制

我正在尝试生成带有一些validation的excel文件，我已经阅读了poi dev指南来实现它。 在实现过程中，我得到了一个exception（ String literals in formulas can't be bigger than 255 characters ASCII ）。 POI将所有下拉选项连接成’0’消除字符串并检查其长度并给我exception。 🙁
我正在使用最新版本的POI 3.8 beta 5。
我的代码是：

 try { HSSFWorkbook wb = new HSSFWorkbook(); HSSFSheet sheet = wb.createSheet("new sheet"); HSSFRow row = sheet.createRow((short) 0); //CellRangeAddressList from org.apache.poi.ss.util package CellRangeAddressList addressList = new CellRangeAddressList(0, 0, 0, 0); DVConstraint dvConstraint = DVConstraint.createExplicitListConstraint(getCountries()); DataValidation dataValidation = new HSSFDataValidation(addressList, dvConstraint); dataValidation.setSuppressDropDownArrow(false); sheet.addValidationData(dataValidation); FileOutputStream fileOut = new FileOutputStream("c:\\test.xls"); wb.write(fileOut); fileOut.close(); } catch (IOException e) { e.printStackTrace(); } 

之后我尝试使用此代码使用XSSFWorkBook：

 XSSFWorkbook wb = new XSSFWorkbook(); XSSFSheet sheet = wb.createSheet("new sheet"); DataValidationHelper validationHelper = new XSSFDataValidationHelper(sheet); DataValidationConstraint constraint = validationHelper.createExplicitListConstraint(getCountries()); CellRangeAddressList addressList = new CellRangeAddressList(0, 0, 0, 0); DataValidation dataValidation = validationHelper.createValidation(constraint, addressList); dataValidation.setErrorStyle(DataValidation.ErrorStyle.STOP); dataValidation.setSuppressDropDownArrow(true); sheet.addValidationData(dataValidation); FileOutputStream fileOut = new FileOutputStream("c:\\test.xlsx"); 

不幸的是，在一个单元格中逗号分隔长字符串的结果没有成功：

但是在excel手动中，我可以使用这个长的国家/地区列表创建下拉列表单元格。
有没有办法用长字符串生成下拉列表，或者API不支持？

Answer 1

我理解，Excel本身不允许输入超过255个字符的validation范围字符串，这不是POI限制。 现在我正在使用命名范围和命名单元格 ，它对我来说正常工作。 所以我不得不把我的validation范围标记放在另一张表（隐藏）中，并从我的真实表中引用了所需的单元格范围。 这是我的工作代码：

 HSSFWorkbook workbook = new HSSFWorkbook(); HSSFSheet realSheet = workbook.createSheet("Sheet xls"); HSSFSheet hidden = workbook.createSheet("hidden"); for (int i = 0, length= countryName.length; i < length; i++) { String name = countryName[i]; HSSFRow row = hidden.createRow(i); HSSFCell cell = row.createCell(0); cell.setCellValue(name); } Name namedCell = workbook.createName(); namedCell.setNameName("hidden"); namedCell.setRefersToFormula("hidden!$A$1:$A$" + countryName.length); DVConstraint constraint = DVConstraint.createFormulaListConstraint("hidden"); CellRangeAddressList addressList = new CellRangeAddressList(0, 0, 0, 0); HSSFDataValidation validation = new HSSFDataValidation(addressList, constraint); workbook.setSheetHidden(1, true); realSheet.addValidationData(validation); FileOutputStream stream = new FileOutputStream("c:\\range.xls"); workbook.write(stream); stream.close(); 

Answer 2

以上代码工作正常。 但是，如果我使用XSSF类而不是HSSF，它就无法在线程中说出Exception

 "main" java.lang.NoSuchMethodError: org.apache.poi.ss.formula.FormulaParser.parse(Ljava/lang/String;Lorg/apache/poi/‌​ss/formula/FormulaParsingWorkbook;II)[Lorg/apache/poi/ss/formula/ptg/Ptg; at org.apache.poi.xssf.usermodel.XSSFName.setRefersToFormula(XSSFName.java:195) at XLDropdown.main(XLDropdown.java:35) 

要使用XSSF接口创建下拉列表，我得到了解决方案

使用apache poi XSSF接口创建下拉列表

Answer 3

Õzbek提供的强大解决方案只需稍加修改即可与NPOI（在.NET上使用C＃）完美配合。

这是我的代码，为C＃编码器提供了便利。 它将一个工作表和位置元素作为输入，并且当它们按列排列时也可以处理多个下拉列表。

 public static void CreateDropDownListForExcel(this ISheet sheet, IList dropDownValues, int startRow, int lastRow, int column) { if (sheet == null) { return; } //Create a hidden sheet on the workbook (using the column as an id) with the dropdown values IWorkbook workbook = sheet.Workbook; string dropDownName = sheet.SheetName + "DropDownValuesForColumn" + column; ISheet hiddenSheet = workbook.CreateSheet(dropDownName); for (int i = 0, length = dropDownValues.Count; i < length; i++) { string name = dropDownValues[i]; IRow row = hiddenSheet.CreateRow(i); ICell cell = row.CreateCell(0); cell.SetCellValue(name); } //Create the dropdown using the fields of the hidden sheet IName namedCell = workbook.CreateName(); namedCell.NameName = dropDownName; namedCell.RefersToFormula = (dropDownName + "!$A$1:$A$" + dropDownValues.Count); DVConstraint constraint = DVConstraint.CreateFormulaListConstraint(dropDownName); CellRangeAddressList addressList = new CellRangeAddressList(startRow, lastRow, column, column); HSSFDataValidation validation = new HSSFDataValidation(addressList, constraint); int hiddenSheetIndex = workbook.GetSheetIndex(hiddenSheet); workbook.SetSheetHidden(hiddenSheetIndex, SheetState.HIDDEN); //Add the Dropdown to the presenting sheet. sheet.AddValidationData(validation); }