C # expert Pleez help!!?

im trying to make a simple web browser could u tell me what is wrong with my code?? the line with the error is the the one that stars with Browser.Navigate(URL...etc.T











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 GoButton_Click(object sender, EventArgs e)


{


System.Object nullObject = 0;


string str = "";


System.Object nullObjStr = str;


Cursor.Current = Cursors.WaitCursor;


Browser.Navigate(URL.Text, ref nullObject, ref nullObjStr, ref nullObjStr, ref nullObjStr);


Cursor.Current = Cursors.Default;








}





private void URL_TextChanged(object sender, EventArgs e)


{


this.Browser.Navigate(this.URL.Text);


}





private void Form1_Load(object sender, EventArgs e)


{


this.URL.Text = "Your Favorite URL";


this.Browser.Navigate(this.URL.Text);


}


}


}

C # expert Pleez help!!?
What is the error?

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