压缩多个excel文件

Question

我需要获取多个excel文件（SSRS报告），将它们放在文件夹中并压缩它。这就是我尝试的方式，但它不起作用：

public ActionResult PricingReports( List<int> productIds )
{
    MemoryStream memStream = new MemoryStream();
    using ( ZipArchive archive = new ZipArchive( memStream, ZipArchiveMode.Update ) )
    {
        foreach ( int id in productIds )
        {
            //preparing single excel file
            ReportModel model = PrepareReportModel( values );

            _ssrs.GetReport( model, "EXCEL" );

            ZipArchiveEntry singleReport = archive.CreateEntry( "PricingReport" + " - " + id );
            using ( BinaryWriter binWriter = new BinaryWriter( singleReport.Open() ) )
            {
                binWriter.Write( model.ReportBits );
            }
        }
    }
    return File( memStream.ToArray(), System.Net.Mime.MediaTypeNames.Application.Octet, "Pricing reports" );
}