正则表达式在VB.NET中仅允许点，字母和破折号

Question

I have that code, and it only dimiss words with spaces and that it starts with +... But I have to allow only dots, letters and dashes... I think that its more simple:

Imports System.Text.RegularExpressions

Public Class Contactos

    ReadOnly pattern As String = "\s([^+\d\,]+),?"

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

        Dim cadena As String = " " & TextBox1.Text & ","

        Dim match As Match = Regex.Match(cadena, pattern)

        Do While match.Success
            frmMain.ListBox1.Items.Add(match.Groups(1).ToString)
            match = match.NextMatch()
        Loop
    End Sub
End Class

What can I do?

Thanks! :)

Answer 1

Please try the following pattern "(?<=(^|,\\s))(?<word>[\\.A-Za-z\\-]+)($|,)" and use named group word to get expected values:

    Do While match.Success
        frmMain.ListBox1.Items.Add(match.Groups("word").ToString)
        match = match.NextMatch()
    Loop

Answer 2

Try:

ReadOnly pattern As String = "\s([\.\-A-Za-z]+),?"

In the first answer the "\\w" pattern will match letters, numbers and underscore. The "A-Za-z" portion I gave you will match letters only.