PowerShell: Sort Drive Encryption Status for Custom Output - arrays

Question

I'm trying to get the encryption status of all drives on a Windows system and sort that list in a custom formatted output. I need this because the output is going to a Nagios server; it messes up the formatting of the standard output for Get-BitLockerVolume and is too long.
Here's what I have so far. I'm trying to sort the output in such a manner that the system drive is listed first and gives the mount point (drive letter) along with the percentage.
[array]$DriveTypes = Get-BitLockerVolume | Sort-Object VolumeType | Select-Object VolumeType
[array]$DriveMounts = Get-BitLockerVolume | Sort-Object VolumeType | Select-Object MountPoint
[array]$WDEPercent = Get-BitLockerVolume | Sort-Object VolumeType | Select-Object EncryptionPercentage
for ($i = 0; $i -lt $DriveTypes.Count; $i++) {
if ($DriveIndex -eq $DriveTypes.Count) {
$TextDriveListing = $TextDriveListing + $DriveMounts.MountPoint+" ("+$DriveTypes.VolumeType+") at "+$WDEPercent.EncryptionPercentage+"%."
}
else {
$TextDriveListing = $TextDriveListing + $DriveMounts.MountPoint+" ("+$DriveTypes.VolumeType+") at "+$WDEPercent.EncryptionPercentage+"%, "
}
if ($WDEPercent.EncryptionPercentage -lt $ReqValue) {
$NoEncryptFlag = 1
}
}
My desired output, for example, is this:
C: (OperatingSystem) at 100%, D: (Data) at 0%.
What I actually end up with is this:
C: D: (OperatingSystem Data) at 100 0%, C: D: (OperatingSystem Data) at 100 0%,
I did try something deriving from an answer to "How to sort a Multi Dimensional Array in Powershell" to test it out, commenting out my aforementioned for block and putting in:
$ListDrives | ForEach-Object {
Get-BitLockerVolume #{
MountPoint = $_[0]
EncryptionPercentage = $_[1]
}
} | Sort-Object VolumeType
Write-Host $ListDrives
That spit out this error:
Cannot index into a null array.
At C:****************.ps1:142 char:3
Get-BitLockerVolume #{
~~~~~~~~~~~~~~~~~~~~~~
CategoryInfo : InvalidOperation: (:) [], RuntimeException
FullyQualifiedErrorId : NullArray
What am I doing wrong? Any suggestions?
Thanks so much in advance!

Answer 1

Try this:
for ($i = 0; $i -lt $DriveTypes.Count; $i++) {
if ($i -eq ($DriveTypes.Count - 1)) {
$TextDriveListing = $TextDriveListing + $DriveMounts[$i].MountPoint+" ("+$DriveTypes[$i].VolumeType+") at "+$WDEPercent[$i].EncryptionPercentage+"%."
}
else {
$TextDriveListing = $TextDriveListing + $DriveMounts[$i].MountPoint+" ("+$DriveTypes[$i].VolumeType+") at "+$WDEPercent[$i].EncryptionPercentage+"%, "
}
if ($WDEPercent[$i].EncryptionPercentage -lt $ReqValue) {
$NoEncryptFlag = 1
}
}
You weren't using the $i from your For Loop to access specific indexes in your collections (i've added [$i] to each of your collection variables to do so). You were also using a variable called $DriveIndex that was never populated and I think this needed to be comparing to $i also, however the logic was also one that would never be true because the For loop would end before it was so (so i've changed the logic to ($i -eq ($DriveTypes.Count - 1)).
Here's a tidier version that I think also gets you the same result:
$TextDriveListing = ''
$Drives = Get-BitLockerVolume | Sort-Object VolumeType | Select VolumeType,MountPoint,EncryptionPercentage
$Drives | ForEach-Object {
$TextDriveListing += "$($_.MountPoint) ($($_.VolumeType)) at $($_.EncryptionPercentage)%,"
If ($_.EncryptionPercentage -lt $ReqValue) { $NoEncryptFlag = 1 }
} -End { $TextDriveListing -Replace ',$','.' }
Uses a single variable for the three properties you wanted to access, rather than putting them in to separate variables which was unnecessary.
Uses a ForEach-Object loop to access each item (and their properties) in that collection via the special token $_.
Uses a single double quoted string for output, with the object/properties accessed via the subexpression operator $().
Puts a comma on the end of each line, but then at the End of the ForEach, uses regex to replace the comma at the end of the line (regex: $ token) with a full stop.
Both sets of code are untested, so may need tweaking.