Powershell Pipeline - return a new Object, that was created within pipline - powershell

Question

I keep running into the same problem again, and i have my default way of handling it, but it keeps bugging me.
Isn't there any better way?
So basicly i have a pipline running, do stuff within the pipline, and want to return a Key/Value Pair from within the pipline.
I want the whole pipline to return a object of type psobject (or pscustomobject).
Here is the way i do it everytime.
I create a hashtable at the beginning of the pipline and add key/Value Pairs from within the pipline to this hashtable using the .Add() method.
Afterwards i create a psobject by passing the hashtbale to New-Object`s -Property Parameter. This gives me the desired result.
Get-Process | Sort -Unique Name | ForEach-Object -Begin { $ht = #{} } -Process {
# DO STUFF
$key = $_.Name
$val = $_.Id
# Add Entry to Hashtable
$ht.Add($key,$val)
}
# Create PSObject from Hashtable
$myAwesomeNewObject = New-Object psobject -Property $ht
# Done - returns System.Management.Automation.PSCustomObject
$myAwesomeNewObject.GetType().FullName
But this seems a bit cluncky, isn't there a more elegant way of doing it?
Something like this:
[PSObject]$myAwesomeNewObject = Get-Process | Sort -Unique Name | ForEach-Object -Process {
# DO STUFF
$key = $_.Name
$val = $_.Id
# return Key/Val Pair
#{$key=$val}
}
# Failed - returns System.Object[]
$myAwesomeNewObject.GetType().FullName
This unfortunally dosn't work, since the pipe returns an array of hashtables, but i hope you know now what iam trying to achieve.
Thanks

Answer 1

Not sure if this is more elegant but just another way of doing it, this uses an anonymous function so $ht will no longer be available after execution, and casts to [pscustomobject] instead of using New-Object:
[pscustomobject] (Get-Process | Sort -Unique Name | & {
begin { $ht = #{ } }
process {
# DO STUFF
$key = $_.Name
$val = $_.Id
# Add Entry to Hashtable
$ht.Add($key, $val)
}
end { $ht }
})

Answer 2

You can also use the -End parameter to convert the final hash table to a pscustomobject as part of the pipeline, without needing to set the whole thing to a variable
$ht[$key]=$val is also a nice shorthand for $ht.Add($key,$val):
Get-Process |
Sort -Unique Name |
Foreach -Begin { $ht = #{} } -Process {
$ht[$_.Name] = $_.Id
} -End {[pscustomobject]$ht} |
## continue pipeline with pscustomobject

Answer 3

Thanks to #Santiago Squarzon and #Cpt.Whale answers, i were able to combine them to create a solution that pleases me:
$myAwesomeNewObject = `
Get-Process | Sort -Unique Name | & {
begin { $ht = #{} }
process {
# DO STUFF
$key = $_.Name
$val = $_.Id
# Add Entry to Hashtable
$ht[$key]=$val
}
end {[pscustomobject]$ht}
}
# Success - System.Management.Automation.PSCustomObject
$myAwesomeNewObject.Gettype().FullName
# And helper Hashtable is NULL thanks to the
# anonym function
$null -eq $ht
Thanks alot Guys

Answer 4

Alternatively you may create a hashtable using Group-Object -AsHashTable:
# Store the PIDs of all processes into a PSCustomObject, keyed by the process name
$processes = [PSCustomObject] (Get-Process -PV proc |
Select-Object -Expand Id |
Group-Object { $proc.Name } -AsHashtable)
# List all PIDs of given process
$processes.chrome
Notes:
Common parameter -PV (alias of -PipelineVariable) makes sure that we can still access the full process object from within the calculated property of the Group-Object command, despite that we have a Select-Object command in between.
The values of the properties are arrays, which store the process IDs of all instances of each process. E. g. $processes.chrome outputs a list of PIDs of all instances of the chrome process.