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PowerShell switch statements are one of the easiest ways to compare an expression to multiple conditions. It’s kind of like nesting multiple if statements, but much prettier to look at and easier to understand. In this comprehensive guide, we go over the details and look at several examples you can use to spruce up your PowerShell scripts.

Throughout this guide, I’m using PowerShell version 7.4.3 (formerly called PowerShell Core). However, all of the examples we go over should also work for Windows PowerShell version 5.1. If something doesn’t run as expected, try running it in the latest version of PowerShell.

What is a switch statement?

A switch statement in PowerShell is a simplified way to compare a value against multiple possible results, similar to multiple nested if statements. If a condition evaluates to true, any associated action executes.

How to use a switch statement in PowerShell

Here’s what the basic syntax of a switch statement looks like.

Now, let’s look at an actual example of a PowerShell switch statement.

Switch vs. if statements

PowerShell switch and if statements are similar in many ways and are often interchangeable with a few formatting differences and parameters. Even performance results aren’t drastically different (though specific situations and more advanced conditions could return greater performance differences).

The most common factor when choosing between a switch and an if statement with PowerShell comes down to readability. In most cases, if you are evaluating more than two or three conditions, switch statements become much easier to read.

This script identifies the current day of the week and returns a menu item depending on the result. You may even recognize this script from my PowerShell if statements article. It’s comprised of several if, elseif, and else statements, which can appear repetitive and convoluted. By comparison, here’s a script that returns the same results but uses a switch statement instead of an if statement.

The switch statement is much more scannable and easier to read. Even though the if statement uses fewer lines, it has to repeat the command and comparison operator throughout the example, making it more difficult to read.

Using the default clause with switch statements

The default clause is a built-in keyword that determines what to do if no match is found. Instead of returning nothing, the default clause is given an action to perform just like any other value. Here’s an example of using the default clause.

Since the expression “teal” doesn’t match any of the other values, it executes the default action.

PowerShell switch parameters

The PowerShell switch statement includes several parameters to help define expressions and input sources. Here are a list of the available switch parameters directly from Microsoft’s help documentation.

Wildcard: Indicates that the condition is a wildcard string. If the match clause is not a string, the parameter is ignored. The comparison is case-insensitive.

Exact: Indicates that the match clause, if it is a string, must match exactly. If the match clause is not a string, this parameter is ignored. The comparison is case-insensitive.

CaseSensitive: Performs a case-sensitive match. If the match clause is not a string, this parameter is ignored.

File: Takes input from a file rather than a <test-expression>. If multiple File parameters are included, only the last one is used. Each line of the file is read and evaluated by the switch statement. The comparison is case-insensitive.

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How to use multiple expressions in a switch statement

Switch statements can evaluate multiple expressions in the same statement. This can be in the form of an array, multiple variables, integers, strings, etc.

When submitting multiple expressions, separate them with a comma. Multiple expressions are evaluated in the order they are written.

Here we evaluate the letters “a,” “b,” and “d.” Both “a” and “b” return true, but “d” doesn’t match any of the conditions.

PowerShell switch break vs. continue

If you don’t want an expression to match more than once, you can either use the continue or break statement. A continue statement stops evaluating the current expression once a match is found; however, it proceeds to evaluate the next expression if there is one available.

In this example, we use the continue statement to limit each expression to match only one condition. Once the second condition evaluates and matches 2, the switch statement moves onto the next value in the variable, eliminating duplicate matches. Here is the result.

If you want to stop the entire switch once a specific condition is met, use the break statement. Here’s what happens if I replace the continue statement with a break statement in the same example.

The break statement stops the switch from evaluating anything after the first condition returns true.

Switch statement examples

What’s that? You’re still here and you want more PowerShell switch statement examples? Well, as any good rock star concedes to their adoring fans chanting encore, I guess I could muster up a couple more examples to keep my fans happy.

Using switch statements to identify running processes

Counting files by file type with the PowerShell switch statement

In this example, the PowerShell script returns the number of specific file types found in a given directory.

Here are the results when I run this script in my test environment.

You can easily add more document types to this script to meet your needs. Also, consider adding a default condition for files with no matching file type listed.

Get-Help about_switch info

Hopefully this guide helps you add to your PowerShell repertoire. If you’re interested in more PowerShell basics, definitely check out our guide on PowerShell loops. And if you’re still stuck using the command line, it’s not too late. We have tons of articles that teach you the PowerShell equivalents of your favorite cmd commands, like our PowerShell equivalent of dsquery article.

Lastly, if you need help running scripts against your managed devices, check out PDQ Connect or PDQ Deploy & Inventory. Connect is an agent-based solution that makes local and remote device management easy. Deploy & Inventory specialize in on-prem device management and don’t require an agent installation.