System Object Error when exporting results to CSV - csv

Question

I am trying to export my results from a compare-object into a csv but I get an error When I export it. It looks ok when I just call it in excel. My guess is whenever there is a output of more than one value the error is placed instead of the value.
Here are my csvs
past.csv
VKEY
V-12345
V-23456
V-1111
current.csv
VKEY
V-12345
V-6789
V-23456
V-256
My new csv should say
Past, Current
V-6789,V-1111
V-256
What I am getting now is
Past, Current
System.Object[],#{vkey=V-1111}
.
$Past = Import-CSV "past.csv"
$Current = Import-CSV "Current.csv"
$pastchange = Compare-Object $Past $Current -Property vkey | Where-Object {$_.SideIndicator -eq '=>'} | Select-Object VKEY
$currentchange = Compare-Object $Past $Current -Property vkey | Where-Object {$_.SideIndicator -eq '<='} | Select-Object VKEY
$obj = New-Object PSObject
$obj | Add-Member NoteProperty Past $pastchange
$obj | Add-Member NoteProperty Current $currentchange
$obj | Export-Csv "ChangeResults.csv" -NoTypeInformation

Answer 1

That System.Object[] displayed in $obj.Past column is simply an array of custom objects similar to #{vkey=V-1111} in $obj.Past column. Proof:
PS D:\PShell> $obj
$obj.Past.Gettype() | Format-Table
$obj.Current.Gettype()
"---"
$obj.Past | ForEach-Object { $_.Gettype() }
Past Current
---- -------
{#{vkey=V-6789}, #{vkey=V-256}} #{vkey=V-1111}
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True Object[] System.Array
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True False PSCustomObject System.Object
---
True False PSCustomObject System.Object
True False PSCustomObject System.Object
My solution makes use of ArrayList Class (.NET Framework):
$csvOutFile = "d:\test\ChangeResults.csv" # change to fit your circumstances
$PastInFile = "d:\test\past.csv"
$CurrInFile = "d:\test\curr.csv"
$Past = Import-CSV $PastInFile
$Curr = Import-CSV $CurrInFile
# compare CSV files and convert results to arrays
$PastCh=#(, <# always return an array #>
$( Compare-Object $Past $Curr -Property vkey |
Where-Object { $_.SideIndicator -eq '=>' } ) |
ForEach-Object { $_ | Select-Object -ExpandProperty vkey }
)
$CurrCh=#(, <# even if no SideIndicator matches #>
$( Compare-Object $Past $Curr -Property vkey |
Where-Object { $_.SideIndicator -eq '<=' } ) |
ForEach-Object { $_ | Select-Object -ExpandProperty vkey }
)
[System.Collections.ArrayList]$csvout = New-Object System.Collections.ArrayList($null)
$auxHash = #{} # an auxiliary hash object
$max = ($CurrCh.Count, $PastCh.Count | Measure-Object -Maximum).Maximum
for ($i=0; $i -lt $max; $i++) {
Try { $auxHash.Past = $PastCh.GetValue($i) } Catch { $auxHash.Past = '' }
Try { $auxHash.Curr = $CurrCh.GetValue($i) } Catch { $auxHash.Curr = '' }
$csvout.Add((New-Object PSObject -Property $auxHash)) > $null
}
$csvout | Format-Table -AutoSize # show content: 'variable $csvout'
$csvout | Export-Csv $csvOutFile -NoTypeInformation
Get-Content $csvOutFile # show content: "output file $csvOutFile"
Output:
PS D:\PShell> D:\PShell\SO\37753277.ps1
Past Curr
---- ----
V-6789 V-1111
V-256
"Past","Curr"
"V-6789","V-1111"
"V-256",""
PS D:\PShell>
Here is an alternative for Try … Catch blocks:
<# another approach instead of `Try..Catch`:
if ($i -lt $PastCh.Count) { $auxHash.Past = $PastCh.GetValue($i)
} else { $auxHash.Past = '' }
if ($i -lt $CurrCh.Count) { $auxHash.Curr = $CurrCh.GetValue($i)
} else { $auxHash.Curr = '' }
#>