write System.IO.Stream to file in vb.net

MargeS · 14-12-2006 02:10PM #1

I am trying to write a System.IO.Stream to a file in vb.net.
I can get it to write the file to the browser successfully but can't figure out how to write/save it to disk.

This part is successful:
objThumbnail.Save(Response.OutputStream, Imaging.ImageFormat.Jpeg)

But it's the next bit I can't do! Any ideas?

txs

Mutant_Fruit · 14-12-2006 04:42PM

First, read the Response.OutputStream into a memorystream so you can use it a few times, call the memorystream memstream (or whatever). Then:

memstream.Seek(0, SeekOrigin.Begin); // set the stream to the start again
objThumbnail.Save(Response.OutputStream, Imaging.ImageFormat.Jpeg)

memstream.Seek(0, SeekOrigin.Begin); // set the stream to the start again
System.IO.File.WriteAllBytes(memstream.ToArray(), @C:\MyDirectory\MyThumbnail.thumb.whatever);

MargeS · 14-12-2006 08:05PM

Dim memstream As MemoryStream = Response.OutputStream
        memstream.Seek(0, SeekOrigin.Begin)
        'objThumbnail.Save(Response.OutputStream, Imaging.ImageFormat.Jpeg)

        'memstream.Seek(0, SeekOrigin.Begin) 'set the stream to the start again
        File.WriteAllBytes("d:\test.jpg", memstream.ToArray)

This hasn't worked and I have tried many variations.
I have put it into try/catch and it doesn't even produce an error that I could start from. It does nothing and its the last part of a long sequence of events that all work until this part.

objThumbnail.Save(Response.OutputStream, Imaging.ImageFormat.Jpeg)

This part on it's own produces a GDI+ error, so I've been trying to figure out a different way to do it.

Mutant_Fruit · 14-12-2006 11:52PM

You need to create a NEW memorystream and then copy the outputstream into that new memorystream, not cast the outputstream as the memorystream.

psuedocode;
byte[] buffer = new byte[response.contentlength];
Response.OutputStream.Read(buffer, 0, response.contentlength);

File.WriteAllBytes("d:\test.jpg", buffer);

MemoryStream s = new MemoryStream(buffer);
s.Seek(0, SeekOrigin.Begin);
objThumbnail.Save(Response.OutputStream, Imaging.ImageFormat.Jpeg)

write System.IO.Stream to file in vb.net

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