This tutorial will show you how to convert a byte array from a stream in C#.NET

You can use the MemoryStream to convert a stream to byte array

public byte[] ConvertStreamToArray(Stream input)
{
    using (MemoryStream ms = new MemoryStream())
    {
        input.CopyTo(ms);
        return ms.ToArray();
    }
}

another version using the Read method to read data from a stream, then write to a buffer

public byte[] ConvertStreamToBytes(Stream input)
{
    byte[] buffer = new byte[16*1024];
    using (MemoryStream ms = new MemoryStream())
    {
        int read;
        while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
        {
            ms.Write(buffer, 0, read);
        }
        return ms.ToArray();
    }
}