ILoggable

public class FormX : System.Windows.Forms.Form
{
    #region Static Members ####################################################
    private static readonly ILog log = LogManager.GetLogger(typeof(FormX));
    #endregion

    #region Members Variables #################################################
    private bool logWatching = true;
    private log4net.Appender.MemoryAppender logger;
    private Thread logWatcher;
    /// <summary>
    /// The TextBox for our logging messages
    /// </summary>
    private System.Windows.Forms.TextBox mLog;
    /// <summary>
    /// Required designer variable.
    /// </summary>
    private System.ComponentModel.Container components = null;
    #endregion

    #region Constructors #################################################
    public FormX()
    {
        //
        // Required for Windows Form Designer support
        //
        InitializeComponent();

        this.Closing += new CancelEventHandler(FormX_Closing);
        logger = new log4net.Appender.MemoryAppender();

        // Could use a fancier Configurator if you don't want to catch every message
        log4net.Config.BasicConfigurator.Configure(logger);

        // Since there are no events to catch on logging, we dedicate
        // a thread to watching for logging events
        logWatcher = new Thread(new ThreadStart(LogWatcher));
        logWatcher.Start();
    }
    #endregion

    // [...]

    private void FormX_Closing(object sender, CancelEventArgs e)
    {
        // Gotta stop our logging thread
        logWatching = false;
        logWatcher.Join();
    }

    private void LogWatcher()
    {
        // we loop until the Form is closed
        while(logWatching)
        {
            LoggingEvent[] events = logger.Events;
            if( events != null && events.Length > 0 )
            {
                // if there are events, we clear them from the logger,
                // since we're done with them
                logger.Clear();
                foreach( LoggingEvent ev in events )
                {
                    StringBuilder builder;
                    // the line we want to log
                    string line = ev.LoggerName + ": " + ev.RenderedMessage+"\r\n";
                    // don't want to grow this log indefinetly, so limit to 100 lines
                    if( mLog.Lines.Length > 99 )
                    {
                        builder = new StringBuilder(mLog.Text);
                        // strip out a nice chunk from the beginning
                        builder.Remove(0,mLog.Text.IndexOf('\r',3000)+2);
                        builder.Append(line);
                        mLog.Clear();
                        // using AppendText since that makes sure the TextBox stays
                        // scrolled at the bottom
                        mLog.AppendText(builder.ToString());
                    }
                    else
                    {
                        mLog.AppendText(line);
                    }
                }
            }
            // nap for a while, don't need the events on the millisecond. 
            Thread.Sleep(500);
        }
    }
}