Looping

Any programming language has the ability to loop through code. This allows it to perform the same action repeatedly without the programmer having to write the code repeatedly.

You'll run across several looping commands in scripts. They are very often used to loop through collections, which are explained in the next section. In each of these looping commands, the code that is executed is included in the curly brackets.

The ForEach command is commonly used in PowerShell in the following format:

ForEach (Item in a collection) {
    Code to execute
}

You'll see the ForEach loop used in this tutorial.

Another looping command that is commonly used is the Do While loop. It will execute code as long as (or while) a condition is met. The format is

Do {
    Code to execute
}
While (condition is true)

Here's a simple example of how a Do While loop could be used to execute code. It creates a variable named $counter and populates it with the number 0. It then outputs the value using the Write-Host line, increments the counter using $counter++, and then checks the value in the While line.

$counter = 0
Do {
Write-Host "Value is" $counter
$counter++
}
While ($counter -lt 5)

The output of the code will be five lines that look like this:

Value is 0
Value is 1
Value is 2
Value is 3
Value is 4