Magicodes.IE之快速导出Excel

前言

总是有很多朋友咨询Magicodes.IE如何基于ASP.NET Core导出Excel，出于从框架的体验和易用性的角度，Magicodes.IE决定对Excel的导出进行独立封装，以便于大家更易于使用，开箱即用。

注意：Magicodes.IE是从框架的易用性和体验的角度对Excel导出进行了封装，但是希望大家先理解原理后再使用。

1.安装包

Install-Package Magicodes.IE.Excel.AspNetCore

2.引用命名空间

using Magicodes.ExporterAndImporter.Excel.AspNetCore;

3.直接使用XlsxFileResult

参考Demo如下所示：

    [ApiController][Route("api/[controller]")]public class XlsxFileResultTests : ControllerBase{/// <summary>/// 使用Byte数组导出Excel文件/// </summary>/// <returns></returns>[HttpGet("ByBytes")]public async Task<ActionResult> ByBytes(){//随机生成100条数据var list = GenFu.GenFu.ListOf<ExportTestDataWithAttrs>(100);var exporter = new ExcelExporter();var bytes = await exporter.ExportAsByteArray<ExportTestDataWithAttrs>(list);//使用XlsxFileResult进行导出return new XlsxFileResult(bytes: bytes);}/// <summary>/// 使用流导出Excel文件/// </summary>/// <returns></returns>[HttpGet("ByStream")]public async Task<ActionResult> ByStream(){//随机生成100条数据var list = GenFu.GenFu.ListOf<ExportTestDataWithAttrs>(100);var exporter = new ExcelExporter();var result = await exporter.ExportAsByteArray<ExportTestDataWithAttrs>(list);var fs = new MemoryStream(result);return new XlsxFileResult(stream: fs, fileDownloadName: "下载文件");}/// <summary>/// 使用泛型集合导出Excel文件/// </summary>/// <returns></returns>[HttpGet("ByList")]public async Task<ActionResult> ByList(){var list = GenFu.GenFu.ListOf<ExportTestDataWithAttrs>(100);return new XlsxFileResult<ExportTestDataWithAttrs>(data: list);}}

如上所示，引用 Magicodes.IE.Excel.AspNetCore之后，导出就会变得如此简单。值得注意的是：

使用XlsxFileResult需引用包Magicodes.IE.Excel.AspNetCore
XlsxFileResult继承自ActionResult，目前支持字节数组、流和泛型集合为参数的Excel文件下载
支持传递下载文件名，参数名fileDownloadName，如不传则自动生成唯一的文件名

核心实现

在Magicodes.IE.Excel.AspNetCore中，我们添加了自定义的ActionResult——XlsxFileResult，核心参考代码如下所示：

    /// <summary>/// Excel文件ActionResult/// </summary>/// <typeparam name="T"></typeparam>public class XlsxFileResult<T> : XlsxFileResultBase where T : class, new(){/// <summary>////// </summary>/// <param name="data"></param>/// <param name="fileDownloadName"></param>public XlsxFileResult(ICollection<T> data, string fileDownloadName = null){FileDownloadName = fileDownloadName;Data = data;}public string FileDownloadName { get; }public ICollection<T> Data { get; }public async override Task ExecuteResultAsync(ActionContext context){var exporter = new ExcelExporter();var bytes = await exporter.ExportAsByteArray(Data);var fs = new MemoryStream(bytes);await DownloadExcelFileAsync(context, fs, FileDownloadName);}}/// <summary>////// </summary>public class XlsxFileResult : XlsxFileResultBase{/// <summary>////// </summary>/// <param name="stream"></param>/// <param name="fileDownloadName"></param>public XlsxFileResult(Stream stream, string fileDownloadName = null){Stream = stream;FileDownloadName = fileDownloadName;}/// <summary>////// </summary>/// <param name="bytes"></param>/// <param name="fileDownloadName"></param>public XlsxFileResult(byte[] bytes, string fileDownloadName = null){Stream = new MemoryStream(bytes);FileDownloadName = fileDownloadName;}public Stream Stream { get; protected set; }public string FileDownloadName { get; protected set; }public async override Task ExecuteResultAsync(ActionContext context){await DownloadExcelFileAsync(context, Stream, FileDownloadName);}}/// <summary>/// 基类/// </summary>public class XlsxFileResultBase : ActionResult{/// <summary>/// 下载Excel文件/// </summary>/// <param name="context"></param>/// <param name="stream"></param>/// <param name="downloadFileName"></param>/// <returns></returns>protected virtual async Task DownloadExcelFileAsync(ActionContext context,Stream stream,string downloadFileName){var response = context.HttpContext.Response;response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";if (downloadFileName == null){downloadFileName = Guid.NewGuid().ToString("N") + ".xlsx";}if (string.IsNullOrEmpty(Path.GetExtension(downloadFileName))){downloadFileName += ".xlsx";}context.HttpContext.Response.Headers.Add("Content-Disposition", new[] {"attachment; filename=" +HttpUtility.UrlEncode(downloadFileName)});await stream.CopyToAsync(context.HttpContext.Response.Body);}}

欢迎大家多多PR并且前来解锁更多玩法。