readme.md

How to create objects from a flat text file.

Answer to a question in /r/Powershell

flatfile.txt

Topic: NBA All Stars
Owners: Foo Owners
Users: User 1
Users: User 2
Topic: NFL MVPs
Owners: Bar Owners
Users: Tony Stark
Users: Mitch Hedberg
Users: Someone Else
Topic: NBA MVPs
Owners: MVP Owners
Users: Jane Smith
Users: John Doe

flatfile2csv.ps1

# see https://www.reddit.com/r/PowerShell/comments/51mhe8/flat_text_file_to_csv/

$flatfile = Get-Content -Path .\flatfile.txt
# this will contain every record
$allrecords = @()
# this will contain the property of the current record.
$record = $null

foreach ( $line in $flatfile ) {
    Switch -Regex ($line) {
        'Topic: (?<topic>.*)' { 
            if ( $record ) {
                # if there's a previous $record, we
                # create the object from it
                $record.users = $record.users -join ', '
                $allrecords += New-Object -TypeName psobject -Property $record
            }
            $record = @{topic=$Matches.topic}
        }
        'Owners: (?<owners>.*)' { $record.owners = $Matches.owners }
        'Users: (?<user>.*)' { $record.users += ,$Matches.user }
    }
}
# We still have one record in memory
# we add it to the list.
$record.users = $record.users -join ', '
$allrecords += New-Object -TypeName psobject -Property $record

# print to screen
$allrecords | select topic,owners,users

# export to CSV file
$allrecords | select topic,owners,users | Export-Csv -Path ".\flatfile.csv" -NoTypeInformation