PowerShell’s Get-Childitem (gci)

Scripting Files with PowerShell’s Get-Childitem (gci)

Sooner or later you need a script which lists the files in a folder.  In DOS we would type: ‘DIR’; the nearest equivalent in PowerShell is gci.  The full name behind the gci alias is Get-ChildItem.  You can take the comparison further, dir /s in DOS, translates to Get-ChildItem -Recurse in PowerShell.

PowerShell Get-ChildItem Topics

• Example 1: List files in the root of the C:\ drive
• Example 2: The Famous GCI -Recurse Parameter
• Trusty Twosome (Get-Help and Get-Member)
• Example 3: List ALL Files, Including Hidden and System
• Example 4: Filter to List Just the System files

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Example 1: To List Files in the Root of the C:\ drive

Here is an example to get started, it will list all the files in the C:\ root.  If you need any help in executing the code, then see here.

Note 1: In this instance C:\ is the root, and Get-Childitem lists any files at this location.

Note 2: Get-Childitem "C:\"  works equally well without the speech marks.  E.g.:
           Get-Childitem C:\   However, you do need the backslash after the colon, and you would need speech marks if the directory contained spaces.

Example 2: The Famous GCI -Recurse Parameter

Outside of PowerShell, recurse is a little known verb which means: rerun.  Inside of PowerShell, Get-ChildItem -Recurse is one of the most famous parameters meaning: repeat the procedure on sub-folders.

The point of example 2b is to list all the dll’s under the Windows folder.  Moreover, it will display their CreationTime, which helps determine if a file is up-to-date.  This technique is particularly useful for troubleshooting .dll files.

Example 2a: The Problem

Our goal is to find all the dlls under the Windows folder.  The problem is that this script does not search the system32 subdirectory.

Note 3: I substituted the alias gci for Get-ChildItem

Note 4: This script lists only 4 dlls; surely there must be more?

Example 2b: The Solution

To find .dlls in the subdirectories let us append the Get-ChildItem -Recurse parameter.

Note 5: I changed Name to FullName so that it would display the subdirectory where you can find the file.  See more on $_.extension.

Note 6: You could silence the error messages by introducing this after -Recurse:
 -ErrorAction SilentlyContinue

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Example 2c: Extra Formatting

This example produces the same result but uses the -f formatting command and the alias Gci.

Note 7: This example also uses three aliases; my principle reason was to make line 3 shorter.  Gci is an alias for our featured command Get-Childitem, while the question mark (?) is an alias for ‘where’. "-EA 4" means error action silently continue.

Note 8: The -Recurse parameter comes directly after the name of the directory.  For completeness, the location should be introduced by the -path parameter, but as this is optional, I have omitted the -Path parameter in this script.  However, this is how to include the -Path parameter.
$Files = gci -Path "C:\Windows\System32" -Recurse.

Trusty Twosome (Get-Help and Get-Member)

When you discover a new PowerShell command, it benefits from being probed with what I call the ‘Trusty Twosome’.  Experiment with Get-Help and Get-Member and unlock new scripting possibilities for Get-Childitem. To see what I mean try these two commands:

Note 9: Get-Help unearths useful parameters such as -Recurse, -exclude, it also reveals hidden files with: -Force.

Note: Get-Member reveals properties that you don’t normally see in explorer, for example, CreationTime.

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Example 3: List ALL Files, Including Hidden and System

Note 10: The key addition is the parameter -Force.  What this does is include hidden and system files.

Note 11: The additional commands enable us to count the files, this makes easier to see prove that -Force really makes a difference.  Double check what I mean by running the script with, and then without, the -Force switch.

See basic PowerShell examples featuring Get-ChildItem »

Example 4: Filter to List Just the System files

Note 12:  We need to employ the comparison parameter -Match "System", rather than -eq "System", this is because System files also have Hidden and other attributes.  Consequently, their attribute does not equal ”System”, although it does contain, or match the word System.

Note 13:  These last two examples employ the .count property rather than using the $i counter of previous scripts.  See more on GCI -Exclude and Where-Object.

Challenge 1:  Repeat the command with and without -Force.

Challenge 2:  Substitute this new ‘where’ clause on line 3: where {$_.attributes -ne "Directory"}. -ne is the opposite of -eq.  Thus this command filters out the directory entry.

Get-Childitem -Recurse can be surprisingly tricky, if this construction is giving you problems, see here for more help on -Recurse

Get-ChildItem Alias ‘Gci’

With Microsoft, there are always at least three ways of doing everything, what seems like redundancy when you are an expert, seems like perspective when you are a beginner.  Get-ChildItem has not one, but three aliases check thus:

Result: dir, ls and gci.

Parameter Aliases for Get-ChildItem
Starting in PowerShell 3.0 you can also use these aliases for PARAMTERS

Get-ChildItem C:\
-d, or -ad (Directory)
-af (File)
-h, -ah (Hidden)
-ar (ReadOnly)
-as (System)

Example 1: Get-ChildItem C:\ -as -force
Example 2: gci D:\ -ad

The Rest of the Item Family

As expected there is an Get-Item cmdlet, but you may not realize there is a Move-Item cmdlet.  PowerShell -Noun or -verb research always throws up at least one surprise.

See more Get-ChildItem examples »

Summary of Get-ChildItem

Get-ChildItem, or its alias gci is an interesting and important PowerShell cmdlet.  Interesting because it has classic parameters such as -Force and -Recurse; important because it's the basis of so many scripts that need to interrogate not only the filesystem but also the registry or certificate store.

See more Microsoft PowerShell file tutorials:

• PowerShell Home   • Add-Content   • Get-Content   • Set-Content  • PowerShell -Filter   • Test-Path

• PowerShell Get-ChildItem   • Get-ChildItem -Include   • Get-ChildItem -Exclude   • Compare-Object

• PowerShell Registry  • Get-Credential  • PowerShell ItemProperty  • PowerShell ItemPropery GCI

Please email me if you have a better example script. Also please report any factual mistakes, grammatical errors or broken links, I will be happy to correct the fault.