使用Web API实现文件下载-优快云博客

本文链接：https://blog.youkuaiyun.com/stoneLSL/article/details/88310085

本文介绍了如何通过Web API处理两种数据源（byte字节流和本地文件）来实现文件下载，重点在于返回HttpResponseMessage的方式。

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web api 文件下载

数据源：

1.byte字节流

var stream = new FileStream(filePath, FileMode.OpenOrCreate);

2.本地文件

var stream = new FileStream(filePath, FileMode.OpenOrCreate);

返回类型：HttpResponseMessage

public HttpResponseMessage DownloadExecll(string fundId)
{
    var fileName ="";
    var bytes = null;
    return GetFileResponse(fileName,bytes);

}
       

 private HttpResponseMessage GetFileResponse(string fileName, byte[] bytes)
{
            HttpResponseMessage response = new HttpResponseMessage(System.Net.HttpStatusCode.OK);
            var mime = System.Web.MimeMapping.GetMimeMapping(fileName);
            var stream = new MemoryStream(bytes);
            response.Content = new StreamContent(stream);
            // 下载服务已有的文件 fileStream
            //var filePath = System.Web.Hosting.HostingEnvironment.MapPath(@"~/App_Data/myfile.xls");
            //var stream = new FileStream(filePath, FileMode.OpenOrCreate);
            // stream 保存到本地文件
            //File.WriteAllBytes(@"C:\xxxx.xlsx", bytes);
            response.Content = new StreamContent(stream);
            bool isFirefox = Request.Headers.UserAgent.ToString()
                                .IndexOf("Firefox", StringComparison.CurrentCultureIgnoreCase) > -1;
            response.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue(mime);
            response.Content.Headers.ContentDisposition =
                    new ContentDispositionHeaderValue("attachment")
                    {
                            FileName = isFirefox ? fileName :
                            HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8)
                    };
            response.Content.Headers.ContentLength = stream.Length;

}