C# da Metodlar

c#

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 WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
 
        }
 
        private void button1_Click(object sender, EventArgs e)
        {
            int a = Convert.ToInt32(textBox1.Text);
            int b = Convert.ToInt32(textBox2.Text);
            int c = Convert.ToInt32(textBox3.Text);
            listBox1.Items.Add("çevre"+cevreyaz(a,b,c));
            listBox1.Items.Add("alan"+alanyaz(a,b,c));
        }
        int cevreyaz(int a, int b, int c)
        {
            return a + b + c;
        }
        double alanyaz(int a, int b, int c)
        {
            double u=(a+b+c)/2.0;
            double alan=0 , hesap ;
            hesap=u*(u-a)*(u-b)*(u-c);
            alan=Math.Pow(alan,1/2.0);
            return alan ;
        }
        void ücgenmi(int a, int b, int c)
        {
            bool k1, k2, k3=
                k1=(a<b+c && a>b-c && a>c-b );
                k2 = ( b<a+c && b>a-c && b>c-a);
                k3 = (c < a + b && c > a - b && c > b - a);
                        if (k1 == true && k2 == true && k3 == true)
       {
              listBox1.Items.Add("üçgendir");
 
       }
else
       {
                            listBox1.Items.Add("üçgen değildir " );
 
       }
 
        }
        void ücgentürü(int a, int b, int c)
        {
            if (a==b && b==c && a==c )
            {
                listBox1.Items.Add("eşkenar üçgen ");
 
            }
            else if (a==b || b==c || a==c)
            {
                listBox1.Items.Add("ikizkenar üçgen");
 
            }
            else
            {
                listBox1.Items.Add("çeşitkenar üçgen");
 
            }
        }
    }
}