Metoder uden parametre

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 Metoder1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        int tal1;
        int tal2;
        int sum;

        private void btnKnap_Click(object sender, EventArgs e)
        {
            ReadNumbers();
            AddUp();
            WriteOut();
        }

        void ReadNumbers()
        {
            tal1 = int.Parse(txtInput1.Text);
            tal2 = int.Parse(txtInput2.Text);
        }

        void AddUp()
        {
            sum = tal1 + tal2;
        }

        void WriteOut()
        {
            lblUd.Text = sum.ToString();
        }
    }
}