Why can not I get Select-Object to work on hashtable right

PowerShell Help
1

I have hashtable which is returned from execution of remote command. Yet when I issue Select-Object command it does not pull those properties out. It does work on some objects and not on others (I execute the same script on range of computers). And I can not figure out what the difference between those.

PS C:\> $b.GetType()

IsPublic IsSerial Name BaseType

True True Hashtable System.Object

PS C:> $b.Keys
LogNameForSource
MachineName
SourceExists
PS C:> $b.Values
Application
DNVAPPSVC1
True
PS C:> $b | Select-Object -Property LogNameForSource, MachineName, SourceExists | ft -AutoSize

LogNameForSource MachineName SourceExists
2

I found what the difference is - one some computers using Invoke-Command returns PSCustomObject and on others it returns HashTable code is below

$temp = {$result= [pscustomobject]@{"MachineName" = $env:ComputerName; "SourceExists" = [bool] $false;"LogNameForSource"=""} if ([System.Diagnostics.EventLog]::SourceExists('dcom')) { $result.SourceExists = $true $result.LogNameForSource = [System.Diagnostics.EventLog]::LogNameFromSourceName("dcom", ".") } return $result }

$a = Invoke-Command -ScriptBlock $temp -ComputerName Server1
PS C:> $a.GetType().Name
PSCustomObject
$a = Invoke-Command -ScriptBlock $temp -ComputerName Server2
PS C:> $a.GetType().Name
Hashtable

3

And a hash table only has Key and Value properties. You can’t select just a particular key using Select-Object.

4

GS,

Check out the official documentation regarding hash tables for examples:

https://technet.microsoft.com/en-us/library/Hh847780.aspx

5

GS, on these computers you probably does not have latest PS

PS C:\Users> $psversiontable
Name Value

[…]
PSVersion 2.0
[…]
PS C:\Users> [pscustomobject]@{aaa=‘aaaa’;bbb=‘bbbb’}
Name Value

bbb bbbb
aaa aaaa
PS C:\Users> ([pscustomobject]@{aaa=‘aaaa’;bbb=‘bbbb’}).gettype()
IsPublic IsSerial Name BaseType

True True Hashtable System.Object

[pscustomobject] was implemented on v3+