Imports System.Text.RegularExpressions
Module Example
Public Sub Main()
Dim pattern As String = "\b(\d{2}-)*(?(1)\d{7}|\d{3}-\d{2}-\d{4})\b"
Dim input As String = "01-9999999 000-333333 777-88-9999"
Console.WriteLine("Matches for {0}:", pattern)
For Each match As Match In Regex.Matches(input, pattern)
Console.WriteLine(" {0} at position {1}", match.Value, match.Index)
Next
End Sub
End Module