上海网站建设服务公司如何查询网站的建设商

安装 依赖库：NPOI

创建XSSFWorkbook和Sheet
设置表头行
添加数据验证：
身份证列用COUNTIF公式确保唯一
地址相关列锁定固定值
学段列设置三级下拉
固定值通过单元格赋值实现
输出

using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using NPOI.SS.Util;
using System.IO;/// <summary>
/// 下载模板
/// </summary>
/// <returns></returns>
public ActionResult DownloadTemplate(DownloadTemplateDto input) {if (input.total< 1) throw new UserFriendlyException("人数不能为0");var stream = GenerateExcel(input.total);var data= stream.ToArray();return new FileContentResult(data, "application/octet-stream");//application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
}private MemoryStream GenerateExcel(int rowTotal)
{rowTotal = rowTotal + 10;//总行数// 1. 创建工作簿和工作表IWorkbook workbook = new XSSFWorkbook();ISheet sheet = workbook.CreateSheet("基础信息");// 创建文本格式样式（用于身份证号列）ICellStyle textStyle = workbook.CreateCellStyle();IDataFormat textFormat = workbook.CreateDataFormat();textStyle.DataFormat = textFormat.GetFormat("@"); // "@" 表示文本格式// 2. 创建列名行// 2. 设置列名（共12列）string[] headers = { "姓名", "身份证号", "现住省", "现住市", "现住区", "联系电话","详细地址", "学校名称", "学校编号", "学段", "年级", "班级" };IRow headerRow = sheet.CreateRow(0);for (int i = 0; i < headers.Length; i++){headerRow.CreateCell(i).SetCellValue(headers[i]);}// 3. 设置数据验证规则IDataValidationHelper validationHelper = sheet.GetDataValidationHelper();// 规则1：身份证号列唯一性验证CellRangeAddressList idRange = new CellRangeAddressList(1, rowTotal, 1, 1); // B列IDataValidationConstraint idConstraint = validationHelper.CreateCustomConstraint("COUNTIF(B:B, B1)=1");IDataValidation idValidation = validationHelper.CreateValidation(idConstraint, idRange);idValidation.CreateErrorBox("重复错误", "身份证号必须唯一！");sheet.AddValidationData(idValidation);// 规则2：固定值验证（省、市、区、学校名称、学校编号）SetFixedValue(sheet, 2, "北京市", rowTotal); // C列：现住省SetFixedValue(sheet, 3, "昌平区", rowTotal); // D列：现住市SetFixedValue(sheet, 4, "A街道", rowTotal); // E列：街道SetFixedValue(sheet, 7, deptName, rowTotal); // H列：学校名称SetFixedValue(sheet, 8, deptId, rowTotal); // I列：学校编号// 规则3：学段下拉选择（小学/初中/高中）CellRangeAddressList stageRange = new CellRangeAddressList(1, rowTotal, 9, 9); // J列IDataValidationConstraint stageConstraint = validationHelper.CreateExplicitListConstraint(new string[] { "小学", "初中", "高中", "高三", "中专", "技校", "大学" });IDataValidation stageValidation = validationHelper.CreateValidation(stageConstraint, stageRange);stageValidation.CreateErrorBox("输入错误", "请选择下拉选中对应值！");sheet.AddValidationData(stageValidation);// 规则4：年级CellRangeAddressList grade = new CellRangeAddressList(1, rowTotal, 10, 10); // K列IDataValidationConstraint gradeConstraint = validationHelper.CreateExplicitListConstraint(new string[] { "一年级", "二年级", "三年级", "四年级", "五年级", "六年级","初一", "初二", "初三", "高一", "高二", "高三", "大一", "大二", "大三", "大四" });IDataValidation gradeValidation = validationHelper.CreateValidation(gradeConstraint, grade);gradeValidation.CreateErrorBox("输入错误", "请选择下拉选中对应值！");sheet.AddValidationData(gradeValidation);for (int rowIndex = 1; rowIndex <= rowTotal; rowIndex++){IRow row = sheet.GetRow(rowIndex) ?? sheet.CreateRow(rowIndex);ICell idCell = row.GetCell(idCardColumnIndex) ?? row.CreateCell(idCardColumnIndex);// 应用文本样式（即使单元格为空）idCell.CellStyle = textStyle;// 如果已有数据，确保以文本格式存储if (idCell.StringCellValue != null){idCell.SetCellValue(idCell.StringCellValue);}
}// 5. 流式输出MemoryStream stream = new MemoryStream();workbook.Write(stream, true);stream.Position = 0; // 重置流位置 return stream;
}// 辅助方法：为整列设置固定值 添加样式参数
private void SetFixedValue(ISheet sheet, int columnIndex, string value, int rowTotal, ICellStyle textStyle)
{for (int rowIndex = 1; rowIndex <= rowTotal; rowIndex++){IRow row = sheet.GetRow(rowIndex) ?? sheet.CreateRow(rowIndex);ICell cell = row.GetCell(columnIndex) ?? row.CreateCell(columnIndex);cell.SetCellValue(value);// 如果是身份证列（索引1），应用文本样式if (columnIndex == 1){cell.CellStyle = textStyle;}}
}

测试

修改下载后的文件后缀为xlsx格式即可打开