Check if a File Exists in Windows PowerShell

Scripting is one of the most fundamental and powerful tools of any developer, system administrator, or geek. Scripting allows us to automate repetitive tasks that would take numerous steps.

PowerShell has been at the forefront of scripting languages in the Windows ecosystem. One of the significant uses of scripting is creating, updating, or deleting files with the filesystem.

However, when working in PowerShell, you might encounter instances where the target file you wish to work on does not exist or already exists. In an automated environment, such a scenario can lead to the script breaking or an error leading to data loss.

In this tutorial, we will learn the various methods and techniques that we can use to check is a given file exists by using Windows PowerShell.

Requirements

To follow along with this post, you will need to have the following:

• PowerShell version 7.0 and above.
• Code Editor.

In this post, we will explore the following methods to check if a file exists using PowerShell.

• PowerShell Test-Path cmdlet
• PowerShell Get-Item cmdlet
• PowerShell System.IO.File class.

We will also explore some examples of how to use the above methods.

Method 1 - Using Test-Path

The Test-Path cmdlet in PowerShell allows us to determine whether a given path’s elements exist. The syntax of the cmdlet is as shown:

Test-Path
    [-Path] <String[]>
    [-Filter <String>]
    [-Include <String[]>]
    [-Exclude <String[]>]
    [-PathType <TestPathType>]
    [-IsValid]
    [-Credential <PSCredential>]
    [-OlderThan <DateTime>]
    [-NewerThan <DateTime>]
    [<CommonParameters>]

The cmdlet returns $True if all the elements of the provided path exist and $False if any are missing. The cmdlet can also allow us to tell whether the specified path syntax is valid or not.

To use this cmdlet to check whether a given file exists, we can use the syntax as shown:

Test-Path -Path "<path\to\file>" -PathType Leaf

For example, suppose we wish to ensure that the file located in C:\users\admin\Desktop\hello.txt exits. We can use the command as shown:

Test-Path -Path "C:\Users\csalem\Desktop\hello.txt" -PathType Leaf

Once we run the command above in the PowerShell, it should return True if the file exits. However, if the file does not exist, it will return False.

NOTE: Using the -PathType Leaf parameter tells the cmdlet that wish to check the provided path as a file and not a directory.

Method 2 - Using the Get-Item Cmdlet

The second method we can use to check whether a given file exists on the filesystem is the Get-Item cmdlet. This cmdlet allows us to get the item at a specified location.

We also have access to the Get-ChildItem cmdlet, which allows us to get the items and child items in one or more specified locations.

Let us start with the Get-Item cmdlet as shown:

Get-Item "Path\to\file"

For example:

Get-Item "C:\Users\csalem\Desktop\hello.txt"

This should return details about the file if it exists as shown:

Directory: C:\Users\csalem\Desktop
Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
-a----         8/25/2023   9:00 AM              6 hello.txt

If the file does not exist, the command will return an error as shown:

Get-Item : Cannot find path 'C:\Users\csalem\Desktop\hello.tt' because it does not exist.
At line:1 char:1
+ Get-Item "C:\Users\csalem\Desktop\hello.tt"

The same functionality applies to the Get-ChildItem cmdlet as shown:

Get-ChildItem -Path "C:\Users\csalem\Desktop\hello.txt"

Method 3 - Using the [System.IO.File]::Exists() Method

One of the most powerful features of PowerShell is the ability to import and use .NET classes and methods in a single call.

One of the methods in the .NET IO.File class is the Exists() method. This method allows us to check whether a file is in the specified path.

The method returns a Boolean true if a file exists and a false if otherwise.

The method definition is as shown:

public static bool Exists (string? path);

We can use the method as shown in the syntax below:

[System.IO.File]::Exists("path\to\file")

An example is as shown:

$file = 'c:\users\csalem\Desktop\hello.txt'
[System.IO.File]::Exists($file)

True

The command above returns true as the file exists on the specified path.

We can also combine the .NET ternary operator for more precise control as shown:

$file = 'C:\users\csalem\Desktop\hello.txt'
[System.IO.File]::Exists($file) ? "The file exists." : "The file does not exist."

If the file exists, the code above will print the first section in this case. Otherwise, the code will print the last string if the result is false.

Conclusion

In this tutorial, you learned how to use the built-in PowerShell cmdlets and .NET methods to check whether a given file exists on the server. This can allow you to provide more error-handling techniques instead of stopping the script from executing if a file does or does not exist on the specified path.