Configuring log4net TextBoxAppender (custom appender) via Xml file

Question

This is in followup to my question: Flexible Logging Interface...

I now want to write a custom log4net appender for a multiline TextBox, for my WinForms 2.0 applicat

Answer 1

Here is a WPF/XAML version of klodoma's answer

  public class TextBoxAppender : AppenderSkeleton {
    private TextBox AppenderTextBox { get; set; }
    private Window window;

    public string WindowName { get; set; }
    public string TextBoxName { get; set; }

    private T FindControl(Control root, string textBoxName) where T:class{
        if (root.Name == textBoxName) {
            return root as T;
        }

        return root.FindName(textBoxName) as T;
    }

    protected override void Append(log4net.Core.LoggingEvent loggingEvent) {
        if (window == null || AppenderTextBox == null) {
            if (string.IsNullOrEmpty(WindowName) ||
                string.IsNullOrEmpty(TextBoxName))
                return;

            foreach (Window window in Application.Current.Windows) {
                if (window.Name == WindowName) {
                    this.window = window;
                }
            }
            if (window == null)
                return;

            AppenderTextBox = FindControl(window, TextBoxName);
            if (AppenderTextBox == null)
                return;

            window.Closing += (s, e) => AppenderTextBox = null;
        }
        window.Dispatcher.BeginInvoke( new Action(delegate {
            AppenderTextBox.AppendText(RenderLoggingEvent(loggingEvent));
        }));
    }

and the log config

Don't forget to give your window a name (must be different to the window type name)