Recursividade em C#

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace matriz
{
public partial class Form1 : Form
{


public Form1()
{
InitializeComponent();
}

int fatorial(int numero)
{
if (numero == 0)
{
return 1;
}
else
{
return numero * fatorial(numero - 1);
}
}



private void btnFatorial_Click(object sender, EventArgs e)
{
txtFatorial.Text =Convert.ToString(fatorial(Convert.ToInt32(txtFatorial.Text)));
}
}
}