format eine Zeichenfolge, usa Telefonnummer in vb.net

Public Shared Function PhoneFormat(ByVal strPhoneNumber As String) As String

' Remove any style characters from the user input
strPhoneNumber = Replace(strPhoneNumber, ")", "")
strPhoneNumber = Replace(strPhoneNumber, "(", "")
strPhoneNumber = Replace(strPhoneNumber, "-", "")
strPhoneNumber = Replace(strPhoneNumber, ".", "")
strPhoneNumber = Replace(strPhoneNumber, Space(1), "")

Dim strFormatedNumber As String = CLng(strPhoneNumber).ToString("(###) ###-####")
Return strFormatedNumber

End Function

Hier ist eine Kombination von Regex und string-Formatierung, das funktioniert ziemlich gut für mich. Fügen Sie einfach Salz auf ein Rezept und es schmeckt SUPER!!!

''' <summary>
'''  returned formats are: 
'''  example1               (620) 123-4567 Ext: 890
'''  example2                     123-4567 Ext: 890
'''  example3               (620) 123-4567 
'''  example4                     123-4567
'''  The user can input a 7 or 10 digit number followed by a character(s) and digits for the extension
''' 
''' </summary>
''' <param name="OriginalNumber"></param>
''' <returns></returns>
''' <remarks></remarks>
Public Function FormatPhone(ByVal OriginalNumber As String) As String

    Dim sReturn As String
    Dim tester() As String
    Dim R As Regex
    Dim M As Match
    Dim sTemp As String

    sReturn = ""
    ' removes anything that is not a digit or letter
    sTemp = UnFormatPhone(OriginalNumber)
    ' splits sTemp based on user input of character(s) to signify an extension i.e. x or ext or anything else you can think of (abcdefg...)
    tester() = Regex.Split(sTemp, "\D+")
    ' if the string was split then replace sTemp with the first part, i.e. the phone number less the extension
    If tester.Count > 1 Then
        sTemp = tester(0)
    End If
    ' Based on the NANP (North American Numbering Plan),  we better have a 7 or 10 digit number.  anything else will not parse
    If sTemp.Length = 7 Then
        R = New Regex("^(?<First>\d{3})(?<Last>\d{4})")
    ElseIf sTemp.Length = 10 Then
        R = New Regex("^(?<AC>\d{3})(?<First>\d{3})(?<Last>\d{4})")
    Else
        Return OriginalNumber
    End If
    ' now format the phone number nice and purtee...
    M = R.Match(sTemp)
    If m.Groups("AC").Length > 0 Then
        sReturn &= String.Format("({0}) {1}-{2}", CStr(m.Groups("AC").Value), CStr(m.Groups("First").Value), CStr(m.Groups("Last").Value))
    Else
        sReturn &= String.Format("{0}-{1}", CStr(m.Groups("First").Value), CStr(m.Groups("Last").Value))
    End If
    If tester.Count > 1 Then
        sReturn &= " Ext: " + tester(1)
    End If
    Return sReturn

End Function

''' <summary>
''' Strips NON ALPHANUMERICS from a string
''' 
''' </summary>
''' <param name="sTemp"></param>
''' <returns></returns>
''' <remarks></remarks>
Public Function UnFormatPhone(ByVal sTemp As String) As String
    sTemp = ClearNull(sTemp)
    Dim sb As New System.Text.StringBuilder
    For Each ch As Char In sTemp
        If Char.IsLetterOrDigit(ch) OrElse ch = " "c Then
            sb.Append(ch)
        End If
    Next
    UnFormatPhone = sb.ToString

End Function

''' <summary>
''' Returns a trimmed string with vbNullChar replaced by a blank
''' </summary>
''' <param name="sTemp"></param>
''' <returns></returns>
''' <remarks></remarks>
Public Function ClearNull(ByRef sTemp As String) As String
    sTemp = Replace(sTemp, vbNullChar, "")
    ClearNull = Trim(sTemp)
End Function