Method "split" not found in [Selected.System.Management.Automation.PSCustomObject] - powershell

Question

in my script I want to read a csv-file into an array and split the text in the first column.
The file consists a table with 2 columns. In the first column there are the personal names with the short Usernames in brackets. In the second column are the position of the user.
User:
Hoch,Susane (HOCH05)
Albrecht, Melanie (ALBRE05)
Department:
Managment
Salesoffice
I read the first column in an array and want to split every char after the first "(". So the I have got "Hoch, Susanne" instead of "Hoch, Susane (HOCH05)".
I get the following error message:
[Selected.System.Management.Automation.PSCustomObject] contains no method with the name "Split".
The type of the variable "$value is:
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True False PSCustomObject System.Object
I can´t find my misstake.
Here is my code:
$Arrayusername_ads_unique = New-Object System.Collections.ArrayList
$AD_User = New-Object System.Collections.ArrayList
$AD_User_table = New-Object System.Collections.ArrayList
$username_AD = New-Object System.Collections.ArrayList
$Arrayusername_ads_unique = Get-Content -Path "C:\temp\Userabgleich\Liste-original\User_ADS-utf8.csv"
$Arrayusername_ads_unique | Out-File C:\temp\Userabgleich\output-temp\User_ADS-utf8.csv -Append -Encoding utf8
$AD_User = Import-CSV 'C:\temp\Userabgleich\output-temp\User_ADS-utf8.csv' -Delimiter ";" | sort User
$AD_User_table = $AD_User | Select-Object User
foreach ($value in $AD_User_table)
{
$value.GetType()
$username_AD = $value.Split("(")
}

Answer 1

You can modify your foreach loop to achieve the results:
foreach ($value in $AD_User_table)
{
($value.user -split "\(")[0]
}
I am splitting on the .user property of $value to retrieve the value you are after in string format. By default, $value is going to be a [PSCustomObject] with a property called User. I am retrieving index 0 ([0]) because your -split match will consume a line of output whether or not you choose to keep the output.
If you are only looping to retrieve this particular result, you can accomplish this without a loop using regex substitution and named captures:
$ad_user_table.user -replace "(?<Name>.*?)\(.*",'${Name}'

Answer 2

since you did not provide a proper CSV to test against, i made a guess at what it would look like. [grin]
what it does ...
uses the .Split() method to split on the (
takes the 1st result of that split
trims away any leading/trailing whitespace
sends the result to the $Names collection
displays the content of that collection
here's the code ...
# fake reading in a CSV file
# in real life, use Import-CSV
$InStuff = #'
User,Department
"Hoch,Susane (HOCH05)","Managment"
"Albrecht, Melanie (ALBRE05)","Salesoffice"
'# | ConvertFrom-Csv
$Names = foreach ($IS_Item in $InStuff)
{
$IS_Item.User.Split('(')[0].Trim()
}
$Names
output ...
Hoch,Susane
Albrecht, Melanie