App.xaml.cs

using System.Windows;

namespace SonicBoard
{
    /// <summary>
    /// Application entry point.
    /// </summary>
    public partial class App : Application
    {
        protected override void OnStartup(StartupEventArgs e)
        {
            AppDomain.CurrentDomain.UnhandledException += (s, args) =>
            {
                LogException(args.ExceptionObject as Exception);
            };

            DispatcherUnhandledException += (s, args) =>
            {
                LogException(args.Exception);
                args.Handled = true;
            };

            try
            {
                base.OnStartup(e);
            }
            catch (Exception ex)
            {
                LogException(ex);
                throw;
            }
        }

        private void LogException(Exception? ex)
        {
            if (ex == null) return;
            try
            {
                string logPath = System.IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "crash.txt");
                System.IO.File.WriteAllText(logPath, $"Time: {DateTime.Now}\nException: {ex.GetType().Name}\nMessage: {ex.Message}\nStackTrace:\n{ex.StackTrace}\n\nInnerException:\n{ex.InnerException?.Message}\n{ex.InnerException?.StackTrace}");
                MessageBox.Show($"Application crashed on startup. Error logged to crash.txt:\n\n{ex.Message}", "SonicBoard Crash Detector", MessageBoxButton.OK, MessageBoxImage.Error);
            }
            catch { }
        }
    }
}