regular expressions

Se namespace System.Text.RegularExpressions klassen Regex i docs.

(der er uden tvivl et eksempel)

'Enter this line in declarations to skip long declarations in code
Imports System.Text.RegularExpressions

Private Function CheckString(ByVal StringVal As String) As Integer

    'Instantiate regex objects
    Dim objRegex As Regex 'Expression validator
    Dim objMatch As Match '

    'Declare paterns for matching
    Dim strEx1 As String = "^[0-9]+$" 'Only chars 0-9 - enum 1
    Dim strEx2 As String = "^[0-9]+[a-zA-Z]+" '0-9 and also a-z (including
                                                  'capitals - enum 2
    Dim strEx3 As String = "^[a-z]+$" 'Only a-z small letters - enum 3

    Dim intReturnVal as Integer=0

    objMatch = objRegex.Match(StringVal, strEx1)
    If objMatch.Success Then
      intReturnVal=1
    End If

    objMatch = objRegex.Match(StringVal, strEx2)
    If objMatch.Success Then
      intReturnVal=2
    End If

    objMatch = objRegex.Match(StringVal, strEx3)
    If objMatch.Success Then
      intReturnVal=3
    End If

    Return intRetVal

End Function

This is just a simple expression validation, you can perform much more complex validations. Search on any search engine for expressionvalidator and you will get bunch of results with examples of different paterns.

Jeg vil tillade mig at ligge et svar.

Tak for hjælpen.