Type casting in PowerShell - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the output of this PowerShell type casting?

Consider the following PowerShell code snippet. What will be the output?

PowerShell

$a = [int]"123"
$b = [string]42
$c = [bool]0
Write-Output "$a,$b,$c"

A 123,42,False

B 123,42,True

C 123,42,0

D 123,42,1

💡 Hint

Remember how PowerShell converts strings to integers and numbers to booleans.

Casting "123" to int results in 123. Casting 42 to string results in "42". Casting 0 to bool results in False because 0 is considered falsey.

📝 Syntax

intermediate

Which option correctly casts a string to a datetime in PowerShell?

You want to convert the string "2024-06-15" to a DateTime object. Which option does this correctly?

A [date]"2024-06-15"

B ConvertTo-DateTime "2024-06-15"

C [datetime]"2024-06-15"

D Cast-DateTime "2024-06-15"

💡 Hint

PowerShell uses square brackets for type casting.

The correct syntax to cast a string to DateTime is [datetime]"string". Options B and C are invalid cmdlets. Option C uses [date], which is not a valid type in PowerShell.

🔧 Debug

advanced

Why does this PowerShell cast fail with an error?

Examine the code below and identify why it causes an error.

PowerShell

$num = [int]"abc"
Write-Output $num

A Because "abc" cannot be converted to an integer, causing a runtime error.

B Because the variable $num is not declared before casting.

C Because Write-Output cannot output variables cast from strings.

D Because the syntax for casting is incorrect; it should be (int)"abc".

💡 Hint

Think about what happens when you try to convert non-numeric text to a number.

Casting "abc" to int fails because "abc" is not a valid number, causing a runtime conversion error.

🚀 Application

advanced

How many items are in the resulting array after this cast?

What is the count of elements in the array after this code runs?

PowerShell

$input = "1,2,3,4"
$array = [int[]]($input -split ',')
$array.Count

A 1

B 4

C 0

D Error

💡 Hint

Splitting the string creates multiple strings, then casting to int array converts each element.

Splitting "1,2,3,4" by comma creates 4 strings. Casting to [int[]] converts each to int, so the array has 4 elements.

🧠 Conceptual

expert

What is the value and type of $result after this cast?

Given the code below, what is the value and type of $result?

PowerShell

$result = [bool][int]"0"

A $result is "False" (String)

B $result is True (Boolean)

C $result is 0 (Integer)

D $result is False (Boolean)

💡 Hint

Casting happens inside out: string to int, then int to bool.

First, "0" is cast to integer 0. Then 0 cast to boolean is False. So $result is Boolean False.