Run WPF application without App.xaml

Delete the existing App.xaml file and write a new class file(lets call it StartUp.cs) that looks like below:
    public class StartUp : Application
    {
        [System.STAThreadAttribute()]
        [System.Diagnostics.DebuggerNonUserCodeAttribute()]
        public static void Main()
        {
            StartUp app = new StartUp();
            app.InitializeComponent();
            app.Run();
        }
        public void InitializeComponent()
        {
            this.StartupUri = new Uri("MainWindow.xaml", System.UriKind.Relative);
        }
    }

Note that this class inherits System.Windows.Application