RESTful Service通过流上传/下载大文件 [英] RESTful Service Upload/Download large file through stream

问题描述

大家好！

我正在尝试创建RESTful服务，该服务通过流上传和下载大文件.我有VS2008/Framework 3.5

下载:
代码段(服务器端):
合同:

Hi all!

I''m trying to create RESTful service which upload and download big files through stream. I have VS2008/Framework 3.5

Download:
Code snippet(Server side):
Contract:

[OperationContract] 
        [WebGet(RequestFormat=WebMessageFormat.Xml, ResponseFormat=WebMessageFormat.Xml,
        UriTemplate = "/DownloadFile/?filename={filename}")]       
        Stream DownloadFile(string filename);

实施:

Implementation:

public Stream DownloadFile(string filename)
        {
            string filenamefull = @"C:\downloads\" + filename;
            using (FileStream fs = new FileStream(filenamefull, FileMode.Open, FileAccess.Read))
            {              
                WebOperationContext ctx = WebOperationContext.Current;
                ctx.OutgoingResponse.ContentType = "application/octet-stream";
                ctx.OutgoingResponse.ContentLength = fs.Length;                
                return fs;
            }
        }

app.config:

app.config:

<webHttpBinding>
        <binding name="streamWebHttpBinding" receiveTimeout="01:00:00"  maxReceivedMessageSize="2147483648"
                 sendTimeout="01:00:00" transferMode="Streamed" />
      </webHttpBinding
><endpoint address="rest" binding="webHttpBinding" contract="EssentialWCF.IRest"  
                  behaviorConfiguration="behaviorRest" bindingConfiguration="streamWebHttpBinding"/>
<endpointBehaviors>
        <behavior name="behaviorRest">
          <webHttp />
        </behavior>
      </endpointBehaviors>

当我执行它时，我得到空的流！如果我将流更改为byte []，则效果很好！
-------------------------------------------------- -------------------------------
上传效果很好，但是当我运行WCF测试客户端时，出现如下错误:

When I execute it I get empty stream! If I change stream to byte[] it works great!
---------------------------------------------------------------------------------
Upload works great, but when I run WCF Test Client I get error like below:

Cannot obtain Metadata from http://localhost:8080/EssentialWCF/mex<br />
<br />
For request in operation UploadFile to be a stream the operation must have a single parameter whose type is Stream.

代码段:
合同:

Code snippet:
Contract:

[OperationContract, WebInvoke(UriTemplate = "/UploadFile/?filename={fileName}")]
        void UploadFile(string fileName, Stream fileContents);

实施:

Implementation:

public void UploadFile(string fileName, Stream fileContents)
        {           
            using (FileStream fs = new FileStream(@"C:\Downloads\" + fileName, FileMode.Create, FileAccess.Write ))
            {             
                CopyStream(fileContents, fs);
            }
}

上面的app.config.

谁能解释我怎么了?

app.config above.

Could anyone explain me what''s wrong?

推荐答案

我解决了下载文件的问题.我不应该使用运算符"using".因为使用"关闭流，而我的函数返回关闭流！

I solved my problem with downloading files. I shouldn''t used operator "using". Because "using" close stream and my function returns closed stream!

public Stream DownloadFile(string filename)
        {
            string filenamefull = @"C:\downloads\" + filename;
            FileStream fs = new FileStream(filenamefull, FileMode.Open, FileAccess.Read);
                        
            return fs;           
        }

不幸的是，上传文件仍然出错！ :(

Unfortunately, uploading file still getting error! :(

这篇关于RESTful Service通过流上传/下载大文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！