' Navigates to the URL in the address box when 
' the ENTER key is pressed while the ToolStripTextBox has focus.
Private Sub toolStripTextBox1_KeyDown( _
    ByVal sender As Object, ByVal e As KeyEventArgs) _
    Handles toolStripTextBox1.KeyDown

    If (e.KeyCode = Keys.Enter) Then
        Navigate(toolStripTextBox1.Text)
    End If

End Sub

' Navigates to the URL in the address box when 
' the Go button is clicked.
Private Sub goButton_Click( _
    ByVal sender As Object, ByVal e As EventArgs) _
    Handles goButton.Click

    Navigate(toolStripTextBox1.Text)

End Sub

' Navigates to the given URL if it is valid.
Private Sub Navigate(ByVal address As String)

    If String.IsNullOrEmpty(address) Then Return
    If address.Equals("about:blank") Then Return
    If Not address.StartsWith("http://") And _
        Not address.StartsWith("https://") Then
        address = "http://" & address
    End If

    Try
        webBrowser1.Navigate(New Uri(address))
    Catch ex As System.UriFormatException
        Return
    End Try

End Sub

' Updates the URL in TextBoxAddress upon navigation.
Private Sub webBrowser1_Navigated(ByVal sender As Object, _
    ByVal e As WebBrowserNavigatedEventArgs) _
    Handles webBrowser1.Navigated

    toolStripTextBox1.Text = webBrowser1.Url.ToString()

End Sub