gistfile1.cs

if (data.Length == 2)
                    {
                        var closeCode = (uint)data.Take(2).ToArray().ToLittleEndianInt();
                        switch (closeCode)
                        {
                            case 1000:
                                // Do something
                                break;
                            case 1001:
                                // Do something
                                break;
                            case 1002:
                                // Do something
                                break;
                            case 1003:
                                // Do something
                                break;
                            default:
                                throw new WebSocketException(WebSocketStatusCodes.ProtocolError);
                        }
                    }