Program to add two numbers in 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 WindowsFormsApplication1
{public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)
{int a,b,c;
a=Convert.ToInt32(textBox1.Text);
b=Convert.ToInt32(textBox2.Text);
c=a+b;
textBox3.Text = (c.ToString());

}
}
}