.NET (Core and Framework)

public partial class Form1 : Form
{
    public Form1() {
        InitializeComponent();
        textBox2.AllowDrop = true;
        Application.ThreadException += OnThreadException;
    }

    void OnThreadException(object sender, ThreadExceptionEventArgs e) {
        MessageBox.Show(e.Exception.Message);
    }

    private void button1_Click(object sender, EventArgs e) {
        throw new ApplicationException("button1_Click");
    }

    private void textBox1_MouseDown(object sender, MouseEventArgs e) {
        DoDragDrop(sender, DragDropEffects.All);
    }

    private void textBox2_DragEnter(object sender, DragEventArgs e) {
        e.Effect = e.AllowedEffect;
    }

    private void textBox2_DragDrop(object sender, DragEventArgs e) {
        MessageBox.Show("I'm here!");
        throw new ApplicationException("You'll never see this :-(");
    }
}