c# - Why does FileStream feed FtpWebRequest but not MemoryStream? -

i'm using msdn example here: http://msdn.microsoft.com/en-us/library/system.net.ftpwebrequest.aspx

i changed filestream memorystream , doesn't read bytes

when change filestream works fine.

any clue?

thanks

        compressmemorystream();         stream requeststream = _request.endgetrequeststream(ar);         const int bufferlength = 2048;         byte[] buffer = new byte[bufferlength];         int count = 0;         int readbytes = 0;                  {             //memorystream _compressedoutstream              //is created/filled 'compressmemorystream()'             readbytes = _compressedoutstream.read(buffer, 0, bufferlength);             requeststream.write(buffer, 0, readbytes);             count += readbytes;         }         while (readbytes != 0);         requeststream.close();         state.request.begingetresponse(             new asynccallback(endgetresponsecallback),             state         ); 

what's value of readbytes on first iteration through loop?

my first guess made same mistake make: writing stream, forgetting rewind beginning before starting read it. if that's case, readbytes 0 on first (and only) loop iteration, because you're @ end of stream -- there's nothing read.

try setting stream.position = 0 before start reading.