c# - Does FileStreamResult close Stream?

Question

My question is similar to this question: Does File() In asp.net mvc close the stream?

I have the follows in C# MVC 4.

FileStream fs = new FileStream(pathToFileOnDisk, FileMode.Open);
FileStreamResult fsResult = new FileStreamResult(fs, "Text");
return fsResult;

Will fs be closed automatically by FileStreamResult? thanks!

Answer 1

Yes. It uses a using block around the stream, and that ensures that the resource will dispose.

Here is the internal implementation of the FileStreamResult WriteFile method:

protected override void WriteFile(HttpResponseBase response)
{
    // grab chunks of data and write to the output stream
    Stream outputStream = response.OutputStream;
    using (FileStream)
    {
        byte[] buffer = new byte[BufferSize];

        while (true)
        {
            int bytesRead = FileStream.Read(buffer, 0, BufferSize);
            if (bytesRead == 0)
            {
                // no more data
                break;
            }

            outputStream.Write(buffer, 0, bytesRead);
        }
    }
}