C# OpenXML使Excel文件可下载

using System;
using System.IO;
using DocumentFormat.OpenXml;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Spreadsheet;

public class ExcelGenerator
{
    public static MemoryStream GenerateExcel()
    {
        // 创建一个内存流，用于保存生成的Excel文件
        MemoryStream stream = new MemoryStream();

        // 创建一个Excel文档
        using (SpreadsheetDocument document = SpreadsheetDocument.Create(stream, SpreadsheetDocumentType.Workbook))
        {
            // 添加一个工作簿
            WorkbookPart workbookPart = document.AddWorkbookPart();
            workbookPart.Workbook = new Workbook();

            // 添加一个工作表
            WorksheetPart worksheetPart = workbookPart.AddNewPart<WorksheetPart>();
            worksheetPart.Worksheet = new Worksheet(new SheetData());

            // 将工作表添加到工作簿
            Sheets sheets = workbookPart.Workbook.AppendChild(new Sheets());
            Sheet sheet = new Sheet() { Id = workbookPart.GetIdOfPart(worksheetPart), SheetId = 1, Name = "Sheet1" };
            sheets.Append(sheet);

            // 保存Excel文档
            workbookPart.Workbook.Save();
        }

        // 将内存流的位置重置为起始位置
        stream.Position = 0;

        return stream;
    }
}