menggunakan radio

Cara menggunakan radio pada VB.2008.

klik button hitung
Public Class Form1

    Dim nilai1, nilai2 As Double

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        nilai1 = TextBox1.Text

        nilai2 = TextBox2.Text

        If RadioButton1.Checked = True Then

            TextBox3.Text = nilai1 + nilai2

        End If

        If RadioButton2.Checked = True Then

            TextBox3.Text = nilai1 - nilai2

        End If

        If RadioButton3.Checked = True Then

            TextBox3.Text = nilai1 * nilai2

        End If

        If RadioButton4.Checked = True Then

            TextBox3.Text = nilai1 / nilai2

        End If

    End Sub

End Class