[SOLVED] How to substitute accented characters when renaming text files using first line in Powershell

How to substitute accented characters when renaming text files using first line in Powershell

I'm trying to batch rename plain text files using the first line of each file. I want to keep only alphanumeric characters in with your help I'm almost there. The only issue is that I need accented characters like é or á to be preserved in a form of their respective not accented characters: e and a (text is in Spanish) or be preserved in the name as they are, not removed. This is what I'm using right now:

Get-ChildItem *.txt | Rename-Item -NewName {
    $firstLine = ($_ | Get-Content -TotalCount 1) -replace '[^a-z0-9 ]'
    '{0}.txt' -f $firstLine
}

Thank you. If possible, please let me know if there is a way to keep the symbol "?" too.

Solution

All you need to do is to add á and é to exclusion list of your replacement, ant they will be preserved:

Get-ChildItem *.txt | Rename-Item -NewName {
    ($_ | Get-Content -TotalCount 1 -Encoding UTF8) -replace '[^a-z0-9éá ]', '' -replace '.*', '$0.txt'
}

As for ? - it is not valid symbol for filename in windows, so I don't see a point there. But you always can do multiple replacement, and replace it with something allowed. Like so:

"asd we'wea?gke é or á? to b" -replace '[^a-z0-9éá ]', '' -replace '\?', '!!!!'