Try Catch

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

namespace WindowsFormsApplication3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                int tal1 = int.Parse(textBox1.Text);
                int tal2 = int.Parse(textBox2.Text);

                int sum = tal1 / tal2;
                label1.Text = sum.ToString();
            }

            catch (System.FormatException)
            {
                MessageBox.Show("formatexception");
            }

            catch (System.DivideByZeroException)
            {
                MessageBox.Show("dividezeo");
            }

            catch (System.Exception)
            {
                MessageBox.Show("generel exception");
            }

            finally
            {
                MessageBox.Show("finally");
            }

        }
    }
}