Listing 1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button1.Click
Dim PhNum, IDNum As String
PhNum = TextBox3.Text
Dim ValidNum As Match
ValidNum = Regex.Match(PhNum, "(\(?\d{3}\)?)[-\s]?(\d{3}[-]\d{4})")
If ValidNum.Success Then
TextBox4.Text = ValidNum.Value & " is a valid phone number. The Area code
is " _ & ValidNum.Groups(1).Value & " the number is " &
ValidNum.Groups(2).Value
Else : TextBox4.Text = "Invalid Phone #"
End If
End Sub