Application.Quit() not work on iOS

[niyouwoxi]

    protected override void RaiseOnCompletedOnDestroy() {
        if (_cancelPingPong != null) {
            _cancelPingPong.Dispose();
            _cancelPingPong = null;
        }

        if (_onRecv != null) {
            _onRecv.OnCompleted();
            _onRecv = null;
        }

        if (!IsConnected)   // Note : Here should be if(IsConnected)
            WebSocket.Close();
    }

[niyouwoxi]

should change to
if(IsConnected)
{
WebSocket.Close();
}
otherwise app can not quit when call Application.Quit() on iOS.