How do I get properties that ONLY have populated values? - powershell

Question

How do I get properties that ONLY have populated values?
So for example if I run
Get-QADUser -Identity "SomeOne" -IncludeAllProperties
the output would of course include.. all properties, including those with and those without values. I want a listing of properties with values only. How is it done generally speaking?
This wouldn't be restricted to Quest Cmdlets, I only use Get-QADUser as an example.

Answer 1

You could try using the built-in (hidden) property of PowerShell objects called PSObject, which includes a property called Properties, i.e. a list of all properties on the parent object.
Maybe easier with an example. Take Get-Process... a process can have many attributes (properties) with or without values. In order to get just the ones with values you do this:
(Get-Process | Select -First 1).PSObject.Properties | ?{$_.Value -ne $null} | FT Name,Value
Note that I limited this to just the first process returned by Get-Process. We then get all the properties defined on that object, filtering where Value is not null and then displaying just the Name and Value for those properties.

Answer 2

To complement Charlie Joynt's helpful answer:
Below is convenience function Remove-NullProperties, which creates custom-object copies of its input objects populated with only the non-$null properties of the input objects.
Example use:
# Sample input collection, with 2 objects with different $null-valued
# properties.
$coll = [pscustomobject] #{ one = 'r1c1'; two = $null; three = 'r1c3' },
[pscustomobject] #{ one = 'r2c1'; two = 'r2c2'; three = $null }
# Output copies containing only non-$null-valued properties.
# NOTE: The `ForEach-Object { Out-String -InputObject $_ }` part is solely
# there to ensure that *all* resulting properties are shown.
# With the default output, only the properties found on the FIRST
# input object would be used in the output table.
$coll | Remove-NullProperties |
ForEach-Object { Out-String -InputObject $_ }
This yields the following - note how the respective null-valued properties were removed:
one three
--- -----
r1c1 r1c3
one two
--- ---
r2c1 r2c2
Remove-NullProperties source code:
<#
.SYNOPSIS
Removes properties with $null values from custom-object copies of
the input objects.
.DESCRIPTION
Note that output objects are custom objects that are copies of the input
objects with copies of only those input-object properties that are not $null.
CAVEAT: If you pipe multiple objects to this function, and these objects
differ in what properties are non-$null-valued, the default output
format will show only the non-$null-valued properties of the FIRST object.
Use ... | ForEach-Object { Out-String -InputObject $_ } to avoid
this problem.
.NOTES
Since the output objects are generally of a distinct type - [pscustomobject] -
and have only NoteProperty members, use of this function only makes sense
with plain-old data objects as input.
.EXAMPLE
> [pscustomobject] #{ one = 1; two = $null; three = 3 } | Remove-NullProperties
one three
--- -----
1 3
#>
function Remove-NullProperties {
param(
[parameter(Mandatory,ValueFromPipeline)]
[psobject] $InputObject
)
process {
# Create the initially empty output object
$obj = [pscustomobject]::new()
# Loop over all input-object properties.
foreach($prop in $InputObject.psobject.properties) {
# If a property is non-$null, add it to the output object.
if ($null -ne $InputObject.$($prop.Name)) {
Add-Member -InputObject $obj -NotePropertyName $prop.Name -NotePropertyValue $prop.Value
}
}
# Give the output object a type name that reflects the type of the input
# object prefixed with 'NonNull.' - note that this is purely informational, unless
# you define a custom output format for this type name.
$obj.pstypenames.Insert(0, 'NonNull.' + $InputObject.GetType().FullName)
# Output the output object.
$obj
}
}

Answer 3

These answers didn't work for me in the case of importing an object from an Infoblox csv file. Some values were the empty string, but not null. Testing whether a property is true or not, seems to work better for me. And the result is an object.
$a = [pscustomobject]#{one='hi';two='';three='there'}
$prop = $a.psobject.Properties | where value | foreach name
$a | select $prop
one three
--- -----
hi there

Answer 4

You first get its properties (since Get-QADUser depends on AD schema, the properties list is dynamic) with get-member -type property, then filter out those that don't have \{.*(get).*\} in its definition (that is, they are not "gettable"), then enumerate the resultant list by name and filter out nulls.
$someone=Get-QADUser -Identity "SomeOne" -IncludeAllProperties
$members=$someone|get-member -type property| where {$_.definition -match '\{.*(get).*\}'}
foreach ($member in $members) {
if ($someone[$member.name] -ne $null) {
write-host $member.name $someone[$member.name]
}
}