Extract Domain from DistiniguishedName using PowerShell

Question

I tried the following code to extract the domain and it worked just fine when defining a variable

$ADS = 'CN=Lamda,OU=OU_Bloquage,DC=Adminstrateur,DC=6NLG-AD'

But things didn't go well when I changed $ADS into

$ADS = Get-ADUser -Identity 'Lamda' -Properties DistinguishedName |
       select DistinguishedName`

The result that I want to have is:

DC=Administrateur,DC=6NLG-AD`

Below is the code that I've wrote

$ADS = Get-ADUser -Identity 'Lamda' -Properties DistinguishedName |
       select DistinguishedName
$pattern = '(?i)DC=\w{1,}?\b'
([RegEx]::Matches($ADS, $pattern) | ForEach-Object { $_.Value }) -join ','

Answer 1

As Ansgar Wiechers and Lee_Daily already pointed out, all you really want is the DistinghuishedName property of a user. The Get-ADUser cmdlet returns this property by default, so to get it as string simply do:

$dn = Get-ADUser -Identity 'Lamda' | Select-Object -ExpandProperty DistinguishedName

$dn will now be a string CN=Lamda,OU=OU_Bloquage,DC=Adminstrateur,DC=6NLG-AD

To get only the part where it starts with DC= from that string there are many options.
For instance:

$DN.Substring($dn.IndexOf("DC="))

Another way could be:

'DC=' + ($DN -split 'DC=', 2)[-1]

Or even something like this wil do it:

($DN -split '(?<![\\]),' | Where-Object { $_ -match '^DC=' }) -join ','

.. and probably a lot more ways to get the desired result