使用DotNetZip从流中提取zip

public void ZipExtract(Stream inputStream, string outputDirectory)
    {

        using (ZipFile zip = ZipFile.Read(inputStream))
        {
            Directory.CreateDirectory(outputDirectory);
            zip.ExtractSelectedEntries("name=*.jpg,*.jpeg,*.png,*.gif,*.bmp", " ", outputDirectory,
                                       ExtractExistingFileAction.OverwriteSilently);
        }
    }
 [HttpPost]
    public ContentResult Uploadify(HttpPostedFileBase filedata)
    {
        var path = Server.MapPath(@"~/Files");
        var filePath = Path.Combine(path, filedata.FileName);
       if (filedata.FileName.EndsWith(".zip"))
        {

            ZipExtract(Request.InputStream,path);

        }
        filedata.SaveAs(filePath); 

            _db.Photos.Add(new Photo
                               {
                                   Filename = filedata.FileName
                               });

        _db.SaveChanges();
        return new ContentResult{Content = "1"};

    }