系统中经常用需要读取Excel文件中的数据，导入到数据库，下面是一个示例。
vs：2022
框架：abpvnext 3.1
把Excel中的数据导入到数据库
/// <summary>
/// 导入
/// </summary>
/// <param name="formFile"></param>
/// <returns></returns>
[HttpPost("DefectiveReasonImport")]
public async Task<IActionResult> DefectiveReasonImportAsync(IFormFile formFile)
{
string resultMsg = string.Empty;
var result = false;
int j = 0;//记录行数
try
{
if (formFile.Length > 0)
{
var stopWatch = new Stopwatch();
stopWatch.Start();
#region 防呆验证
//将excel表格中的数据转化为dataTable数据
var getDataTable = NpoiExcelHelper.helper.ExcelToDataTable(formFile.OpenReadStream(), Path.GetExtension(formFile.FileName), out result, out resultMsg);
if (getDataTable.Rows.Count <= 0) throw new Exception($"Excel表中无数据可导入");
var columnData = getDataTable.AsEnumerable()
.Select(row => row.Field<string>("编码"))
.ToList()
;
for (int i = 0; i < getDataTable.Rows.Count; i++)
{
if (getDataTable.Rows[i][0].ToString() == "") throw new Exception($"第[{i + 2}]行，编码不可为空");
if (getDataTable.Rows[i][1].ToString() == "") throw new Exception($"第[{i + 2}]行，不良原因不可为空");
var query = _defectiveReasonRepository.Where(d => d.Code == getDataTable.Rows[i][0].ToString());
if (query.Any())
throw new Exception($"第[{i + 2}]行，表中已存在编码[{getDataTable.Rows[i][0].ToString()}]");
}
//var codeColumnNullOrEmpty = columnData.Where(d => string.IsNullOrEmpty(d));
//if (codeColumnNullOrEmpty.Any()) throw new Exception($"编码不可为空");
var codeColumnGroupList = columnData.GroupBy(d => d)
.Where(d => d.Count() > 1)
.Select(d => d.Key)
.ToList()
;
if (codeColumnGroupList != null && codeColumnGroupList.Count > 0) throw new Exception($"编码存在重复[{codeColumnGroupList.JoinAsString(",")}]");
//var nameColumnNullOrEmpty = columnData.Where(d => string.IsNullOrEmpty(d));
//if (nameColumnNullOrEmpty.Any()) throw new Exception($"不良原因不可为空");
#endregion
#region 向数据库新增数据
for (int i = 0; i < getDataTable.Rows.Count; i++)
{
j = i;
var defectiveReasonCreateDto = new DefectiveReasonCreateUpdateDto
{
Code = getDataTable.Rows[i][0].ToString(),
Name = getDataTable.Rows[i][1].ToString(),
Status = (getDataTable.Rows[i][2] != null && !string.IsNullOrEmpty(getDataTable.Rows[i][2].ToString())) ? Convert.ToBoolean(getDataTable.Rows[i][2]) : true
};
var defectiveReason = ObjectMapper.Map<DefectiveReasonCreateUpdateDto, DefectiveReason>(defectiveReasonCreateDto);
defectiveReason.ChangeCreateUser(DateTime.Now, CurrentUser.Id.ToString());
await _defectiveReasonRepository.InsertAsync(defectiveReason);
}
#endregion
stopWatch.Stop();
resultMsg = $"Excel导入成功,耗费总时长{stopWatch.Elapsed.TotalSeconds}秒，总共导入{getDataTable.Rows.Count}条数据";
}
else
{
resultMsg = "Excel表中无数据可导入！";
}
}
catch (Exception e)
{
await CurrentUnitOfWork.RollbackAsync();
result = false;
resultMsg = $"{e.Message}";
}
return Ok(new { status = result ? 0 : 1, message = resultMsg });
}Excel帮助类
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Text;
namespace Imagine.Mes.MesBase.Application.CommonTool
{
/// <summary>
/// Excel帮助类
/// </summary>
public class NpoiExcelHelper
{
private static NpoiExcelHelper _excelImportHelper;
public static NpoiExcelHelper helper
{
get => _excelImportHelper ?? (_excelImportHelper = new NpoiExcelHelper());
set => _excelImportHelper = value;
}
/// <summary>
/// 读取excel表格中的数据,将Excel文件流转化为dataTable数据源
/// 默认第一行为标题
/// </summary>
/// <param name="stream">excel文档文件流</param>
/// <param name="fileType">文档格式</param>
/// <param name="isSuccess">是否转化成功</param>
/// <param name="resultMsg">转换结果消息</param>
/// <returns></returns>
public DataTable ExcelToDataTable(Stream stream, string fileType, out bool isSuccess, out string resultMsg)
{
isSuccess = false;
resultMsg = "Excel文件流成功转化为DataTable数据源";
var excelToDataTable = new DataTable();
try
{
//Workbook对象代表一个工作簿,首先定义一个Excel工作薄
IWorkbook workbook;
//XSSFWorkbook 适用XLSX格式，HSSFWorkbook 适用XLS格式
#region 判断Excel版本
switch (fileType)
{
//.XLSX是07版(或者07以上的)的Office Excel
case ".xlsx":
workbook = new XSSFWorkbook(stream);
break;
//.XLS是03版的Office Excel
case ".xls":
workbook = new HSSFWorkbook(stream);
break;
default:
throw new Exception("Excel文档格式有误");
}
#endregion
var sheet = workbook.GetSheetAt(0);
var rows = sheet.GetRowEnumerator();
var headerRow = sheet.GetRow(0);
int cellCount = headerRow.LastCellNum;//最后一行列数（即为总列数）
//获取第一行标题列数据源,转换为dataTable数据源的表格标题名称
for (var j = 0; j < cellCount; j++)
{
var cell = headerRow.GetCell(j);
excelToDataTable.Columns.Add(cell.ToString());
}
//获取Excel表格中除标题以为的所有数据源，转化为dataTable中的表格数据源
for (var i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++)
{
var dataRow = excelToDataTable.NewRow();
var row = sheet.GetRow(i);
if (row == null) continue; //没有数据的行默认是null
for (int j = row.FirstCellNum; j < cellCount; j++)
{
if (row.GetCell(j) != null)//单元格内容非空验证
{
#region NPOI获取Excel单元格中不同类型的数据
//获取指定的单元格信息
var cell = row.GetCell(j);
switch (cell.CellType)
{
//首先在NPOI中数字和日期都属于Numeric类型
//通过NPOI中自带的DateUtil.IsCellDateFormatted判断是否为时间日期类型
case CellType.Numeric when DateUtil.IsCellDateFormatted(cell):
dataRow[j] = cell.DateCellValue;
break;
case CellType.Numeric:
//其他数字类型
dataRow[j] = cell.NumericCellValue;
break;
//空数据类型
case CellType.Blank:
dataRow[j] = "";
break;
//公式类型
case CellType.Formula:
{
HSSFFormulaEvaluator eva = new HSSFFormulaEvaluator(workbook);
dataRow[j] = eva.Evaluate(cell).StringValue;
break;
}
//布尔类型
case CellType.Boolean:
dataRow[j] = row.GetCell(j).BooleanCellValue;
break;
错误
//case CellType.Error:
// dataRow[j] = HSSFErrorConstants.GetText(row.GetCell(j).ErrorCellValue);
// break;
// //其他类型都按字符串类型来处理（未知类型CellType.Unknown，字符串类型CellType.String）
default:
dataRow[j] = cell.StringCellValue;
break;
}
#endregion
}
}
excelToDataTable.Rows.Add(dataRow);
}
isSuccess = true;
}
catch (Exception e)
{
resultMsg = e.Message;
}
return excelToDataTable;
}
}
}
