C# WCF REST使用jquery下载pdf

我试图使用jQueryAjax调用从WCFREST服务下载pdf文件，但我认为存在编码问题

下面是服务接口方法定义

[OperationContract]
    [WebInvoke(
        BodyStyle = WebMessageBodyStyle.Bare,
       ResponseFormat = WebMessageFormat.Json,
       RequestFormat = WebMessageFormat.Json, 
        Method="POST", 
        UriTemplate = "DownloadFile")]
    Stream DownloadFile(RequestDownloadFile fileDownload);

然后是实施

 public Stream DownloadFile(RequestDownloadFile fileDownload)
 {
       DBCepPortaleEntities cepPortale = CEP.DAL.DbConnections.GetConnessionePortale(ConnString); //connection with entity framework to SQLServer DB

        var cerco = from cc in cepPortale.WEB_DOCUMENTI
                    where cc.IdDocumento == fileDownload.ID
                    select cc; //retrieving a Pdf VARBINARY Field
        if (cerco.Count() > 0)
        {



            WEB_DOCUMENTI doc = cerco.First();


            String nomeFile = @"test.pdf";
            String tmp = Encoding.Default.GetString(doc.DocPDF);
            File.WriteAllText(nomeFile, tmp, Encoding.Default);//test: pdf file is written correctly and I can read it
            WebOperationContext.Current.OutgoingResponse.ContentType = "application/pdf";
            WebOperationContext.Current.OutgoingResponse.Headers.Add("Content-disposition", "inline; filename=circolare" + fileDownload.ID + ".pdf");
            WebOperationContext.Current.OutgoingResponse.Headers.Add("Content-Transfer-Encoding", "binary");
            WebOperationContext.Current.OutgoingResponse.Headers.Add("Content-Encoding", "none");

            FileStream f = new FileStream(nomeFile, FileMode.Open);
            int length = (int)f.Length;
            WebOperationContext.Current.OutgoingResponse.ContentLength = length;
            byte[] buffer = new byte[length];
            int sum = 0;
            int count;
            while ((count = f.Read(buffer, sum, length - sum)) > 0)
            {
                sum += count;
            }
            f.Close();
            return new MemoryStream(buffer); 
       }
        else
            return null;
 }

此方法正确写入名为“test.pdf”的pdf文件

现在我尝试使用ajax调用来使用它：

$.ajax({
                    method: "POST",
                    url: "http://testwcfcircolari.bresciapaghe.it/Service.svc/DownloadFile",
                    data: '{"Token":"abc", "ID":"20"}',
                    contentType: "application/json",
                    success: function (response, status, xhr) {
                        console.log(response);
                        //self.settings.onSuccessStart(response, status, xhr, self);

                        // Check if a filename is existing on the response headers.
                        var filename = "";
                        var disposition = xhr.getResponseHeader("Content-Disposition");
                        if (disposition && disposition.indexOf("attachment") !== -1) {
                            var filenameRegex = /filename[^;=\n]*=(([""]).*?\2|[^;\n]*)/;
                            var matches = filenameRegex.exec(disposition);
                            if (matches != null && matches[1])
                                filename = matches[1].replace(/[""]/g, "");
                        }

                        filename = "prova.pdf";


                        var type = xhr.getResponseHeader("Content-Type");
                        var blob = new Blob([response], { type: "application/pdf; charset=UTF-8" });

                        if (typeof window.navigator.msSaveBlob !== "undefined") {
                            // IE workaround for "HTML7007: One or more blob URLs were revoked by closing the blob for which they were created. These URLs will no longer resolve as the data backing the URL has been freed.
                            window.navigator.msSaveBlob(blob, filename);
                        } else {
                            var URL = window.URL || window.webkitURL;
                            var downloadUrl = URL.createObjectURL(blob);
                            alert(filename);
                            if (filename) {
                                // Use HTML5 a[download] attribute to specify filename.
                                var a = document.createElement("a");
                                // Safari doesn"t support this yet.
                                if (typeof a.download === "undefined") {
                                    window.location = downloadUrl;
                                } else {
                                    a.href = downloadUrl;
                                    a.download = filename;
                                    document.body.appendChild(a);
                                    a.click();
                                }
                            } else {
                                window.location = downloadUrl;
                            }
                            //console.log(downloadUrl);
                            setTimeout(function () {
                                URL.revokeObjectURL(downloadUrl);
                            }, 100); // Cleanup
                        }
                        // Final custom event.
                        //self.settings.onSuccessFinish(response, status, xhr, self, filename);
                    },
                    error: function (XMLHttpRequest, textStatus, errorThrown) {
                        alert('Error occurred while opening fax template' + XMLHttpRequest + " " +
                              +textStatus + " " + errorThrown);
                    }
                });

结果是一个pdf文件与原始文件具有相同的页面，但内容全部为空。 用文本编辑器查看下载的pdf的内容，它与初学者文件不同

有什么建议吗？ 谢谢。

C#

JS

装订

<bindings>
  <webHttpBinding>
    <binding name="MyWcfRestService.WebHttp" maxBufferSize="2147483637"
             maxBufferPoolSize="2147483637"
             maxReceivedMessageSize="2147483637"
             transferMode="Streamed"
             sendTimeout="00:05:00">
      <readerQuotas  maxDepth="2147483637"
                     maxStringContentLength="2147483637"
                     maxArrayLength="2147483647"
                     maxBytesPerRead="2147483647"
                     maxNameTableCharCount="2147483637"/>
      <security mode="None" />
    </binding>
  </webHttpBinding>
</bindings>

---

非常感谢！通过这种方式，我将使用GET方法来检索文件，但我需要传递令牌以确保客户端获得了访问所确定文件的权限：在GET-In时传递令牌不安全。有办法吗？

function downloadfile(filepath)
 {    
 var url="https://myfile.ololo?v="+filepath;
 window.open(url,"windowname","width:400,height:300");
 }

<bindings>
  <webHttpBinding>
    <binding name="MyWcfRestService.WebHttp" maxBufferSize="2147483637"
             maxBufferPoolSize="2147483637"
             maxReceivedMessageSize="2147483637"
             transferMode="Streamed"
             sendTimeout="00:05:00">
      <readerQuotas  maxDepth="2147483637"
                     maxStringContentLength="2147483637"
                     maxArrayLength="2147483647"
                     maxBytesPerRead="2147483647"
                     maxNameTableCharCount="2147483637"/>
      <security mode="None" />
    </binding>
  </webHttpBinding>
</bindings>