Question

我创建了WebAPI，它使用closedxml nuget返回一个excel文件。基本上它将我的DataTable转换为excel。我在下面提到几个链接，

How to return a file (FileContentResult) in ASP.NET WebAPI
Returning binary file from controller in ASP.NET Web API

问题： excel没有问题。但是当我通过webAPI将其作为HttpResponseMessage返回时下载相同内容时，excel文件已损坏。它说，“文件已损坏，无法打开”:(

我的代码：

    [System.Web.Http.AcceptVerbs("GET", "POST")]
    public HttpResponseMessage ExportExcel()
            {                 
                     DataTable scoredRecords = Getdt();
                     if (scoredRecords.Rows.Count > 0)
                        {
                            var path = @"C:\Raghav\asdf.xlsx";
                            XLWorkbook wb = new XLWorkbook();
                            wb.Worksheets.Add(scoredRecords, "sample");
                            // excel getting generated on server properly-No issues.
                            wb.SaveAs(path);
                            HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
                            var stream = new FileStream(path, FileMode.Open);
                            result.Content = new StreamContent(stream);
                            result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
                            {
                                FileName = "sample.xlsx"
                            };
                            result.Content.Headers.ContentLength = stream.Length;
                            //tried with "application/ms-excel" also
                            result.Content.Headers.ContentType =
                                new MediaTypeHeaderValue("application/octet-stream");
                            return result;
                        }

               }

服务器上生成的excel没有问题。只有通过webAPI下载的excel文件已损坏。无法弄清楚问题.. 任何帮助赞赏!! ：）

Answer 1

试试这个：

    [HttpGet]
    public HttpResponseMessage Export()
    {
        using (var wb = new XLWorkbook())
        using (MemoryStream ms = new MemoryStream())
        {
            wb.Worksheets.Add("sample").FirstCell().SetValue("some value");

            wb.SaveAs(ms);

            HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
            result.Content = new ByteArrayContent(ms.GetBuffer());
            result.Content.Headers.ContentLength = ms.Length;
            result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
            {
                FileName = "sample.xlsx"
            };
            result.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
            return result;
        }
    }

Answer 2

我看到的一个问题是：

 var stream = new FileStream(path, FileMode.Open);

您正在发送FileStream。除此之外，您可以尝试使用byte []：

byte[] excelData  = File.ReadAllBytes(path);
result.Content = new StreamContent(excelData);

你可以尝试一下。

在WebAPI中将HttpResponseMessage作为excel文件返回的问题

2 个答案: