Datasheet

UNDERSTAND THE BASICS OF POWERSHELL 27
Administering Service Delivery
PART I
If you were to run this code in a PowerShell script, the output would read
Current Number: 0
Current Number: 1
Current Number: 2
 e Do statement loops through the code inside the curly brackets for as long as
the condition speci ed in the While statement is valid. In this example, the Do
loop will keep going as long as the
$counter variable is less than 3 ( -lt 3 ). A er
$counter reaches 3, the loop stops, and therefore only the numbers 0, 1, and 2
are displayed. With a Do ... While loop, the code inside the curly brackets is
executed  rst, and then the condition determining whether it should keep going is
evaluated.
On the other hand, a
Do ... Until loop processes the condition  rst. To under-
stand this, we’ll turn the previous code into a
Do ... Until loop:
$counter = 0
Do
{
Write-Host “Current Number: $counter”
$counter++;
} Until ($counter -gt 3)
 is time, the Do loop will continue to process until $counter is greater than 3.
Before the code in the Do loop is processed even once, the condition is evaluated to
make sure $counter is still 3 or less.  e following is the output if this code is run
in a script:
Current Number: 0
Current Number: 1
Current Number: 2
Current Number: 3
A er the script displays that the current number is 3, $counter is incremented
to 4.  is causes the condition ($counter -gt 3) to be met because 4 is greater
than 3, and the Do loop is no longer processed.
Conditionals
In addition to loops, you can use conditionals to make decisions inside your scripts.
One conditional that you’ll probably use o en is
If ... Else .  e If statement
tests whether something is true. If it is, it executes some code. If not, the
If
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