public void binary_writer() { Assert.Throws <ArgumentNullException>(() => StreamExtensions.BinaryWriter(null)); var bytes = Guid.NewGuid().ToByteArray(); var stream = new MemoryStream(); using (var writer = stream.BinaryWriter()) { Assert.True(ReferenceEquals(writer.BaseStream, stream)); writer.Write(bytes); } Assert.True(stream.ToArray().SequenceEqual(bytes)); Assert.Throws <ObjectDisposedException>(() => stream.ReadByte()); }