操作Excel是一个比较常见的业务场景，本篇将使用EPPlus简单演示一个导入导出的示例。

EPPlus开源地址：https://github.com/EPPlusSoftware/EPPlus

在项目中添加EPPlus组件

Install-Package EPPlus

导入

先准备一个Excel文件，将其内容读取出来，并序列化成JSON字符串进行返回。

[HttpPost]
public List<ExcelDemoDto> Import([FromForm] ImportExcelInput input)
{var list = new List<ExcelDemoDto>();using (var package = new ExcelPackage(input.ExcelFile.OpenReadStream())){// 获取到第一个Sheet，也可以通过 Worksheets["name"] 获取指定的工作表var sheet = package.Workbook.Worksheets.First();#region 获取开始和结束行列的个数，根据个数可以做各种校验工作// +1 是因为第一行往往我们获取到的都是Excel的标题int startRowNumber = sheet.Dimension.Start.Row + 1;int endRowNumber = sheet.Dimension.End.Row;int startColumn = sheet.Dimension.Start.Column;int endColumn = sheet.Dimension.End.Column;#endregion// 循环获取整个Excel数据表数据for (int currentRow = startRowNumber; currentRow <= endRowNumber; currentRow++){list.Add(new ExcelDemoDto{AAA = sheet.Cells[currentRow, 1].Text,BBB = sheet.Cells[currentRow, 2].Text,CCC = sheet.Cells[currentRow, 3].Text,DDD = sheet.Cells[currentRow, 4].Text,EEE = sheet.Cells[currentRow, 5].Text,FFF = sheet.Cells[currentRow, 6].Text});}}return list;
}public class ExcelDemoDto
{public string AAA { get; set; }public string BBB { get; set; }public string CCC { get; set; }public string DDD { get; set; }public string EEE { get; set; }public string FFF { get; set; }
}public class ImportExcelInput
{public IFormFile ExcelFile { get; set; }
}

导出

[HttpGet]
public async Task<string> Export()
{using var package = new ExcelPackage();var worksheet = package.Workbook.Worksheets.Add("sheet1");var headers = new string[] { "AAA", "BBB", "CCC", "DDD", "EEE", "FFF" };for (int i = 0; i < headers.Length; i++){worksheet.Cells[1, i + 1].Value = headers[i];worksheet.Cells[1, i + 1].Style.Font.Bold = true;}// 模拟数据var list = new List<ExcelDemoDto>();for (int i = 1; i <= 10; i++){list.Add(new ExcelDemoDto{AAA = $"A{i}",BBB = $"B{i}",CCC = $"C{i}",DDD = $"D{i}",EEE = $"E{i}",FFF = $"F{i}"});}// 支持各种直接获取数据的方法// worksheet.Cells.Load*...int row = 2;foreach (var item in list){worksheet.Cells[row, 1].Value = item.AAA;worksheet.Cells[row, 2].Value = item.BBB;worksheet.Cells[row, 3].Value = item.CCC;worksheet.Cells[row, 4].Value = item.DDD;worksheet.Cells[row, 5].Value = item.EEE;worksheet.Cells[row, 6].Value = item.FFF;row++;}// 通常做法是，将excel上传至对象存储，获取到下载链接，这里将其输出到项目根目录。var path = Path.Combine(Directory.GetCurrentDirectory(), $"excel.xlsx");await package.GetAsByteArray().DownloadAsync(path);return path;
}