PSCustomObject

PSCustomObject is a minimal object representation over System.Object. Custom properties are allowed as NoteProperty.

In the following example, the PSCustomObject created has the same member as default [object] except the NoteProperty Foo.

[object]::new() | gm
[PSCustomObject]@{ Foo = 'I am a NoteProperty!' } | gm

Why Do We Need it

Differ from HashTable as a dictionary, [PSCustomObject] is a representation for object literal. The must-know is [PSCustomObject] maps to the same type as [psobject], System.Management.Automation.PSObject. The only valid usage is marking one HashTable as System.Management.Automation.PSCustomObject. Other possible usages of [PSCustomObject] is bascially pointless.

WARNING

Do not use PSCustomObject if case-sensitive keys matter, name of extended properties are not case-sensitive, use HashTable instead.

Creation

PSCustomObject borrows the syntax from HashTable with a casting.

$john = [PSCustomObject] @{
    Name = 'John Smith'
    Age = 18
}

From HashTable

You can explicitly convert a HashTable to PSCustomObject

$table = @{
    Foo = 'foo'
}

$obj = [PSCustomObject]$table 

Or use New-Object, but this might be slower.

$obj = New-Object -TypeName PSObject -Property $table

Shallow Copy

$john = [PSCustomObject] @{
    Name = 'John Smith'
    Age = 18
}

$smith = $john.psobject.Copy()

Add New Members

You can't directly add new properties after declaration using dot accessor. One should use Add-Member to append new members.

$obj | Add-Member -MemberType NoteProperty -Name PropName -Value Value

NOTE

All members of a [pscustomobject] should be extended properties, you can inspect them using $obj.psextended

Enumerating Properties

$obj.psobject.properties | foreach { $_.Value = 0 }