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Fileresult buffered to memory

I am trying to return large files through an ActionResult controller and have implemented my own FileResult class, as shown below.

    public class StreamedFileResult : FileResult
{
    private string _FilePath;

    public StreamedFileResult(string filePath, string contentType)
        : base(contentType)
    {
        _FilePath = filePath;
    }

    protected override void WriteFile(System.Web.HttpResponseBase response)
    {
        using (FileStream fs = new FileStream(_FilePath, FileMode.Open, FileAccess.Read))
        {
            int bufferLength = 65536;
            byte[] buffer = new byte[bufferLength];
            int bytesRead = 0;

            while (true)
            {
                bytesRead = fs.Read(buffer, 0, bufferLength);

                if (bytesRead == 0)
                {
                    break;
                }

                response.OutputStream.Write(buffer, 0, bytesRead);
            }
        }
    }
}

However, the problem I ran into is that the whole file seems to be buffered into memory. What do I need to do to prevent this?

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2 answers

, . , , . , , IIS , , . .

FileInfo path = new FileInfo(filePath);

// user will not see a progress if content-length is not specified
response.AddHeader("Content-Length", path.Length.ToString());
response.Flush();// do not add anymore headers after this...


byte[] buffer = new byte[ 4 * 1024 ]; // 4kb is a good for network chunk

using(FileStream fs = path.OpenRead()){
   int count = 0;
   while( (count = fs.Read(buffer,0,buffer.Length)) >0 ){
      if(!response.IsClientConnected) 
      {
          // network connection broke for some reason..
          break;
      }
      response.OutputStream.Write(buffer,0,count);
      response.Flush(); // this will prevent buffering...
   }
}

, 4kb , 4kb.

+8

. Content-Length . DO, response.OutputStream, response. ASP.NET MVC ( , 5) "-: ".

byte[] buffer = new byte[ 4 * 1024 ]; // 4kb is a good for network chunk

using(FileStream fs = path.OpenRead()){
   int count = 0;
   while( (count = fs.Read(buffer,0,buffer.Length)) >0 ){
      if(!response.IsClientConnected) 
      {
          // network connection broke for some reason..
          break;
      }
      response.OutputStream.Write(buffer,0,count);
      response.OutputStream.Flush();
      response.Flush(); // this will prevent buffering...
   }
}

, .

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