C# da web browser yazmak

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

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            object a=null;

            axWebBrowser1.Navigate(textBox1.Text, ref a, ref a, ref a, ref a);

        }

        private void button2_Click(object sender, EventArgs e)
        {
            axWebBrowser1.GoBack();

        }

        private void button3_Click(object sender, EventArgs e)
        {
            axWebBrowser1.GoForward();

        }

        private void button4_Click(object sender, EventArgs e)
        {
            textBox1.Text = "www.google.com.tr";
        
            axWebBrowser1.Navigate(textBox1.Text);

        
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            textBox1.Text = "www.abdurrahmantunc.blogspot.com";
            button1.Text = "git";
            button2.Text = "ileri";
            button3.Text = "geri";
            button4.Text = "ana sayfa";

        }
    }

}