When writing about PowerShell, one of the toughest things is ensuring that a script runs consistently on different computers. A script may not necessarily run the same way on someone else’s computer as it does on mine. Oftentimes, this problem can arise due to the requirement for external dependencies.
For instance, if a script requires loading a module or calling on an external data file or other dependency, you need to specify the path and filename in PowerShell. Herein lies the problem: a file’s location on my computer doesn’t guarantee it’s the same place on yours. As such, a hardcoded path can lead to issues.
Locate and Read a File When Its Location Is Unknown
In this scenario, the first step is to use the Get-ChildItem command to locate the file. Here are the commands I would use to find the file:
Set-Location C:$File=Get-ChildItem Example.txt -Recurse -ErrorAction SilentlyContinueThe first command, “Set-Location C:,” instructs PowerShell to navigate to the root folder. The second command uses the Get-ChildItem cmdlet to search for the file in question. By using the Recurse parameter, we indicate to PowerShell that we want to search within any subfolders, as well.
We include the ErrorAction parameter because there may be folders that PowerShell lacks access to. When the Get-ChildItem cmdlet encounters one of these folders, it typically generates an error message. However, by setting the ErrorAction to SilentlyContinue, we can suppress these errors and produce a cleaner output.
$FileLocation = $File.DirectoryName
File Location 1
The $FileLocation variable now contains the file’s path.
So, with the file’s location stored in the $FileLocation variable, let’s get back to the task of reading and displaying the Example.txt file. There are a few different ways that I could do this. The simplest option would likely be to extract the file’s full name (which includes both the path and filename) from the $File variable. Then, I could use the Get-Content command to read the file.
Here is what that sequence of commands might look like:
Set-Location C:$File=Get-ChildItem Example.txt -Recurse -ErrorAction SilentlyContinue$FileLocation = $File.FullNameGet-Content $FileLocation
File Location 2
I have displayed the file’s contents despite the file’s unknown location.
Use PowerShell’s Location Stack
Set-Location C:$File=Get-ChildItem Example.txt -Recurse -ErrorAction SilentlyContinue$FileLocation = $File.DirectoryNameSet-Location $FileLocationGet-Content Example.txt
File Location 3
This is another way that you can read a file from an unknown location.
About the Author(s)
Brien Posey is a bestselling technology author, a speaker, and a 20X Microsoft MVP. In addition to his ongoing work in IT, Posey has spent the last several years training as a commercial astronaut candidate in preparation to fly on a mission to study polar mesospheric clouds from space.
