Stream.CopyTo method
Posted by Davy Brion on April 29th, 2008
No, Stream does not have a useful CopyTo method 
unless…. :
public static class Extensions
{
public static void CopyTo(this Stream source, Stream target)
{
if (!source.CanRead) throw new ArgumentException(“source can not be read”, “source”);
if (!target.CanWrite) throw new ArgumentException(“target can not be written to”, “target”);
source.Position = 0;
while (source.Position < source.Length)
{
var buffer = new byte[4096];
int bytesRead = source.Read(buffer, 0, buffer.Length);
target.Write(buffer, 0, bytesRead);
}
}
}
now you can do:
stream.CopyTo(fileStream);
If there is a way to copy the contents of one stream to another in the .NET framework, please let me know 