Metoder med parametre og returnering

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();
        }

        private void btnKnap_Click(object sender, EventArgs e)
        {
            int tal1 = ReadNumbers(1);
            int tal2 = ReadNumbers(2);

            int sum = AddUp(tal1, tal2);

            WriteOut(sum);
        }

        int ReadNumbers(int temp)
        {
            if (temp == 1)
            {
                int tal = int.Parse(txtInput1.Text);
                return tal;
            }

            if (temp == 2)
            {
                int tal = int.Parse(txtInput2.Text);
                return tal;
            }

            return 0;
        }

        int AddUp(int temp1, int temp2)
        {
            int sum = temp1 + temp2;

            return sum;
        }

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