Imports System.IO
Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        WebBrowser1.Navigate(TextBox1.Text)
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim source As [String] = ("viewsource.txt")
        Dim writer As StreamWriter = File.CreateText(source)
        writer.Write(WebBrowser1.DocumentText)
        writer.Close()
        Process.Start("notepad.exe", source)
    End Sub
End Class