Home » Tip Bank

Language: VB
Expertise: Intermediate

Dec 20, 2005

This VB function returns the DNS domain name (westcoast.mycorp.com) from the passed LDAP distinguishedName (CN=Administrator,DN=Users,DC=westcoast,DC=mycorp,DC=com).

Function DN2DomainName(ByVal strDN As String)
    On Error Resume Next

    Dim strDomainName As String
    Dim strDNParts() As String
    Dim intI As Integer
    
    strDomainName = ""
    strDNParts = Split(strDN, ",")
    ReDim Preserve strDNParts(UBound(strDNParts))
    
    ' Work backwords through DN to assemble domain name
    For intI = UBound(strDNParts) To 0 Step -1
        If (InStr(UCase(strDNParts(intI)), "DC=")) Then
            strDomainName = "." & Replace(strDNParts(intI), "DC=", "") & strDomainName
        Else
            Exit For ' Short circuit when we run out of "DC=" parts
        End If
    Next
    
    ' Chop off leading '.'
    strDomainName = Right$(strDomainName, Len(strDomainName) - 1)
    
    DN2DomainName = strDomainName

End Function

Editor's Note: This code does not check to make sure the strDomainName variable has a leading period before chopping it off, nor does it check whether the final result actually fits the form of a DNS domain name, but it will work if given proper data.