Powershell阵列：HOWTO Dedup输出

Question

When I run this parser script on my contacts.xml, which shows one line per user, I get multiple instances of the same data. I only want a single entry for the same data. How do I dedup the data before it writes to the CSV?

#https://stackoverflow.com/questions/29999682/powershell-parsing-a-text-file
$input = Get-Content $env:USERPROFILE\Downloads\contacts.xml\Downloads\contacts.xml
$array = @()
$input | % {
    $writeobj = $false
    $obj = New-Object System.Object
    if ($_ -match 'email*') {
        $Email = ($_ -split ':')[1]
    }
    if ($_ -match 'FN*') {
        $NAME = ($_ -split ':')[1]
        $writeobj = $true
    }
    if ($writeobj) {
        $obj | Add-Member -Type NoteProperty -Name Email -Value $Email
        $obj | Add-Member -Type NoteProperty -Name Name -Value $NAME
        $array += $obj
    }
    Write-Host $Name, $email
}
$array | Export-Csv -Path C:\scripts\reports\test.csv -NoTypeInformation

I expect this to produce single entries but I get duplicates (and they don't line up right either). (And yes I checked the XML file for single entries)

Answer 1

Select the unique objects.

$array |
    Select-Object -Property * -Unique |
    Export-Csv -Path 'C:\scripts\reports\test.csv' -NoType

As a side note, you may want to avoid appending to an array in a loop, as that is bound to perform poorly. Just pipe your ForEach-Object loop directly into Export-Csv .

Answer 2

I figured it out. I REVERSED the $obj Add-Member variables *that fixed the order) and added another " $writeobj = $true " line to the FN match, and VOILÀ no more dupes. Is that weird or what?

#https://stackoverflow.com/questions/29999682/powershell-parsing-a-text-file
$input = Get-Content $env:USERPROFILE\Downloads\contacts.xml $array =
@() $input | % {
    $writeobj = $false
    $obj = New-Object System.Object
    If ($_ -match 'email') {
        $Email = ($_ -split ':')[1]
        $writeobj = $true
    }
    If ($_ -match 'FN') {
        $NAME = ($_ -split ':')[1]
        $writeobj = $true # <-- right here
    }
    If ($writeobj){
        $obj | Add-Member -type NoteProperty -name Email -value **$NAME**
        $obj | Add-Member -type NoteProperty -name Name -value **$Email**
        $array += $obj
    }
    Write-Host $Name, $email } $array | Export-Csv -path C:\scripts\reports\test.csv -NoTypeInformation