Updating Active directory DN in csv records with Powershell - powershell

Question

I'm completely stuck on how to update multiple rows in a CSV file with new values.. the issue is as follows, I import an active directory csv export file into my powershell which has roughly 500 users, like so:
$Users = Import-CSV "C:\Users\administrator\userExport.csv"
I then need to update the DN column so that they have the new active directory structure on the new domain
Current structure:
DN:
-----------------
CN=John Smith,OU=Users,DC=XTR,DC=ORG
Required new domain structure
DN:
-----------------
CN=John Smith,OU=Users,OU=Administration,DC=RTS,DC=LIVE,DC=LOCAL
The trouble is I have no idea how I can sequentially go through the entries in this CSV files to update only the necessary elements of the entry via powershell, any help with this would be much appreciated.
Sample line from csv file:
DN objectClass instanceType
-- ------------ ------------
CN=John Smith,OU=Users,DC=XTR,DC=ORG user 4
Apologies, I know how vague the request is but I'm sure there must be an elegant way of doing this but my powershell knowledge is extremely limited.
Thanks for your time.

Answer 1

Import-Csv will convert each row in the CSV to an object with properties corresponding to the column headers and the column value of the current row. This makes them easy to manipulate:
$Users = Import-CSV "C:\Users\administrator\userExport.csv"
$Users |ForEach-Object {
# Update DN column value
$_.DN = $_.DN -replace ',DC=XTR,DC=ORG$', ',OU=Administration,DC=RTS,DC=LIVE,DC=LOCAL'
# Output modified object
$_
} |Export-Csv C:\Users\administrator\userExportModified.csv -NoTypeInformation

Answer 2

You should put your CSV sample "as is", and not trying to format it. How can we know if the CSV is well-formed ?
I am trying to answer anyway, based on a well-formed CSV, with default delimiter (comma) :
Import-CSV "C:\Users\administrator\sourceUsers.csv" | ForEach {
$_.DN = $_.DN -replace "OU=Users,DC=XTR,DC=ORG","OU=Users,OU=Administration,DC=RTS,DC=LIVE,DC=LOCAL"
# ^
# Are you sure it is actually 'OU' here and not 'CN'
$_
} | Export-Csv "C:\Users\administrator\destinationUsers.csv" -NoTypeInformation -Enconding UTF8
If there is another delimiter, eg semi colon :
Import-CSV "C:\Users\administrator\sourceUsers.csv" -Delimiter ';' | ForEach {
$_.DN = $_.DN -replace "OU=Users,DC=XTR,DC=ORG","OU=Users,OU=Administration,DC=RTS,DC=LIVE,DC=LOCAL"
# ^
# Are you sure it is actually 'OU' here and not 'CN'
$_
} | Export-Csv "C:\Users\administrator\destinationUsers.csv" -NoTypeInformation -Enconding UTF8
Edit :
Mathias answered during I was typing my own one :), I keep it only because of my remarks about CSV and the 'OU=Users...'