Is it possible to alter part of a variable based on its value?

March 18, 2022

I have a script that grabs a list of AD usernames for members of a student group and allocates those as an array of $students

Later the script will need to take those usernames and input them into a URL

$students = Get-ADGroupMember -Identity "GG_LHS All Students" | Select-Object -ExpandProperty SamAccountName | Sort-Object SamAccountName

foreach ($student in $students)
{
    foreach ($OneDriveAdmin in $OneDriveAdmins)
Set-SPOUser -Site https://mydomain-my.sharepoint.com/personal/$($student)_mydomain_co_uk

In the cases where we have duplicate usernames, our naming scheme adds increments in the format of .1 and .2, but I need to change the ".1" to a "_1" to work in the URL.

My initial thinking is an IF statement during the $students declaration
IF SamAccountName is like '.1' replace '.1' with '_1'

Is this possible to do via powershell?

>Solution :

You could add this check in your loop, if student matches a dot followed by any amount of digits (\.(\d+)), replace for the same digits but prepending and underscore instead (-replace $Matches[0], "_$($Matches[1])"):

foreach($student in $students) {
    if($student -match '\.(\d+)') {
        $student = $student -replace $Matches[0], "_$($Matches[1])"
    }

    # rest of your code here
}

See https://regex101.com/r/fZAOur/1 for more info.