Powershell free disk space for drives without drive letter - powershell

Question

I am working on a power shell script based on http://www.powershellneedfulthings.com/?p=36 to check the disk space for volumes that do not have a driver letter assigned.
The script works pretty well, but I'd like to filter that only drives are shown that have less than 10% free disk space. I'm running into troubles using the where-object filter with hash tables.
# calculations for displaying disk size information
$TotalGB = #{Name="Capacity(GB)";expression={[math]::round(($_.Capacity/ 1GB),2)}}
$FreeGB = #{Name="FreeSpace(GB)";expression={[math]::round(($_.FreeSpace / 1GB),2)}}
$FreePerc = #{Name="Free(%)";expression={[math]::round(((($_.FreeSpace / 1GB)/($_.Capacity / 1073741824)) * 100),0)}}
# array declarations
$volumes = #()
# import server names to check
$servers = (Get-Content .\servers.txt)
# check disk space for volumes without drive letter
foreach ($server in $servers){
$volumes += Get-WmiObject -computer $server win32_volume | Where-Object {$_.DriveLetter -eq $null -and $_.Label -ne "System Reserved"}
}
$volumes | Select SystemName, Label, $TotalGB, $FreeGB, $FreePerc | Format-Table -AutoSize
What I tried is:
Where-Object {$FreePerc -le 10}
The current output is:
SystemName Label Capacity(GB) FreeSpace(GB) Free(%)
---------- ----- ------------ ------------- ----
SERVER01 X:\data\ 9.97 0.89 9
SERVER01 X:\log\ 9.97 1.20 12
SERVER01 X:\info\ 9.97 3.49 35
I'd like to only show the volumes that have less than 10% free disk space. So in this case, only the first entry should be shown.
Thanks!

Answer 1

I think the where clause variable $FreePerc is the issue. Arco had the right idea.
$volumes | Select SystemName, Label, $TotalGB, $FreeGB, $FreePerc | Where-Object {$_.'Free(%)' -le 10} | Format-Table -AutoSize
I put the property in single quotes because i think PowerShell would try to evaluate (%) otherwise. Also to make Arco's solution work it might just be easier to call the Name propery of $FreePerc. That way you only have to update one location
$volumes | Select SystemName, Label, $TotalGB, $FreeGB, $FreePerc | Where-Object {$_.($FreePerc.Name) -le 10} | Format-Table -AutoSize