"This stream does not support seek operations"

Question

I get a stream form a web service:

Stream resultStream = WebServiceEntities.GetAttachment(attachmentId);

enter image description here

I need to convert this stream into a byte array but

Attempt # 1

byte[] resultBytes = null;
using (Stream stream = resultStream)
{
    using (MemoryStream ms = new MemoryStream())
    {
        int count = 0;
        do
        {
            byte[] buf = new byte[1024];
            count = stream.Read(buf, 0, 1024);
            ms.Write(buf, 0, count);
        } while (stream.CanRead && count > 0);
        resultBytes = ms.ToArray();
    }
}

Attempt # 2:

var memoryStream = new MemoryStream();
resultStream.CopyTo(memoryStream);
byte[] resultBytes = memoryStream.ToArray();

In both cases the (byte[] resultBytes) always returns an empty byte array, does anyone know what is causing this to happen? Is there something wrong with the Stream the web service returns?

Have you tried putting the stream position at 0? `resultStream.Position = 0`. — Marcus Vinicius, Feb 21 '13 at 19:58
@Marcus Hello Marcus, I can't do that, If I assign Position=0 to it, I get the following exception: "This stream does not support seek operations." — Eric Bergman, Feb 21 '13 at 20:02
The data in `m_ReadBuffer` may well just be SOAP stuff - its presence doesn't indicate that the attachment had any actual data. — Jon Skeet, Feb 21 '13 at 20:05
@JonSkeet So the Stream returned by the web service might be wrong? — Eric Bergman, Feb 21 '13 at 20:06
@EricBergman: No, it might just be empty - the problem may be somewhere completely different. I suggest you look at the raw response from the server (e.g. via Wireshark or Fiddler) to see what's happening. — Jon Skeet, Feb 21 '13 at 20:10
Set `memoryStream.Position` to 0 after you do the `CopyTo`. See http://stackoverflow.com/q/3702448/56778 — Jim Mischel, Feb 21 '13 at 20:32
@JimMischel That didn't work either, the byte array still returns empty. — Eric Bergman, Feb 21 '13 at 21:51
Have you single-stepped in attempt #1 to confirm that bytes are actually being read? — Jim Mischel, Feb 21 '13 at 22:02
I have the same exact problem, have you found any solution yet? — ForceMagic, May 28 '13 at 22:27

"This stream does not support seek operations"

0 Answers0