Logging control

public partial class LoggingControl : UserControl
{
    private MemoryAppender _logAppender;
    private Thread _loggingThread;
    private bool _isLogging;

    public delegate void AppendToLogTextboxDelegate(LoggingEvent loggingEvent);

    public MemoryAppender LogAppender
    {
        get { return _logAppender; }
        set
        {
            _logAppender = value;

            if (_logAppender != null)
                Reset();
        }
    }

    public bool IsLogging
    {
        get { return _isLogging; }
        set
        {
            _isLogging = value;

            if (!_isLogging)
            {
                if (_loggingThread != null)
                    _loggingThread.Join();
            }
            else
            {
                Reset();
            }
        }
    }

    public LoggingControl()
    {
        InitializeComponent();

        logTextbox.ReadOnly = true;
        _isLogging = false;

        Disposed += new EventHandler(LoggingControl_Disposed);
    }

    private void LoggingControl_Disposed(object sender, EventArgs e)
    {
        StopLogging();
    }

    private void Reset()
    {
        logTextbox.Clear();

        if (_loggingThread != null)
        {
            StopLogging();
        }

        _loggingThread = new Thread(new ThreadStart(StartLogging));
        _loggingThread.Start();
    }

    private void StartLogging()
    {
        _isLogging = true;

        while (_isLogging)
        {
            LoggingEvent[] events = _logAppender.GetEvents();

            if (events != null && events.Length > 0)
            {
                _logAppender.Clear();

                foreach (LoggingEvent loggingEvent in events)
                {
                    BeginInvoke(new AppendToLogTextboxDelegate(AppendToLog), new object[] { loggingEvent });
                }
            }

            Thread.Sleep(500);
        }
    }

    private void AppendToLog(LoggingEvent loggingEvent)
    {
        string line = loggingEvent.Level + "\t- " + loggingEvent.LoggerName + ": " + loggingEvent.RenderedMessage +
                      "\n";

        if (logTextbox.Lines.Length > 99)
        {
            logTextbox.Text.Remove(0, logTextbox.Text.IndexOf('\n') + 1);
        }

        Color lineColor = LineColorByLevel(loggingEvent.Level);

        logTextbox.SelectionStart = logTextbox.TextLength;
        logTextbox.SelectionColor = lineColor;
        logTextbox.AppendText(line);
        logTextbox.SelectionColor = Color.Black;
    }

    private Color LineColorByLevel(Level level)
    {
        if (level == Level.Info)
            return Color.Green;
        else if (level == Level.Debug)
            return Color.Blue;
        else if (level == Level.Warn)
            return Color.DarkCyan;
        else if (level == Level.Fatal)
            return Color.Red;

        return Color.Black;
    }

    private void StopLogging()
    {
        _isLogging = false;
        _loggingThread.Join();
    }
}