Environment variables in PowerShell - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get the value of the PATH environment variable.

PowerShell

Write-Output $Env:[1]

Drag options to blanks, or click blank then click option'

AHOME

BTEMP

CUSER

DPATH

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase variable names like $Env:path which is case-sensitive.

Trying to access environment variables without $Env: prefix.

The $Env:PATH variable holds the system PATH environment variable.

2fill in blank

medium

Complete the code to set a new environment variable named MY_VAR with value 'Hello'.

PowerShell

$Env:[1] = '[2]'

Drag options to blanks, or click blank then click option'

AMY_VAR

BHello

CTEMP

DUSER

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect variable names like PATH instead of MY_VAR.

Not using quotes around string values.

To create or update an environment variable, assign a value to $Env:VariableName. Here, MY_VAR is the variable name and 'Hello' is the value.

3fill in blank

hard

Fix the error in the code to correctly append a directory to the PATH environment variable.

PowerShell

$Env:PATH = $Env:PATH + ';' + [1]

Drag options to blanks, or click blank then click option'

A$NewFolder

BNewFolder

C'C:\NewFolder'

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name that is not defined.

Including quotes inside the concatenation causing literal quotes in PATH.

To append a directory path, use the full path string with quotes inside the concatenation. The path must be a string like 'C:\NewFolder'.

4fill in blank

hard

Fill both blanks to check if the environment variable MY_VAR exists and print its value if it does.

PowerShell

if ($Env:[1]) { Write-Output $Env:[2] } else { Write-Output 'Variable not found' }

Drag options to blanks, or click blank then click option'

AMY_VAR

BPATH

CTEMP

DUSER

Attempts:

3 left

💡 Hint

Common Mistakes

Checking one variable but printing another.

Using variable names that do not exist.

Checking $Env:MY_VAR tests if the variable exists. Printing the same variable outputs its value.

5fill in blank

hard

Fill all three blanks to create a new environment variable, check if it exists, and print a message with its value.

PowerShell

$Env:[1] = '[2]'
if ($Env:[3]) { Write-Output "Value is $Env:[3]" } else { Write-Output 'Not set' }

Drag options to blanks, or click blank then click option'

AMY_VAR

BHelloWorld

DPATH

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names for setting and checking.

Forgetting to quote the string value.

First, set $Env:MY_VAR to 'HelloWorld'. Then check if $Env:MY_VAR exists and print its value.

Practice

1. What is the correct way to access the environment variable PATH in PowerShell?

easy

A. Use PATH$

B. Use get-env PATH

C. Use env(PATH)

D. Use $env:PATH

Solution

1. Step 1: Understand PowerShell environment variable syntax

   PowerShell uses $env:VARIABLE_NAME to access environment variables.

2. Step 2: Apply syntax to PATH variable

   To get the PATH variable, write $env:PATH.

3. Final Answer:

   Use $env:PATH -> Option D

4. Quick Check:

   Environment variable access = $env:VARIABLE [OK]

Hint: Remember: environment variables use $env: prefix in PowerShell [OK]

Common Mistakes:

• Using incorrect syntax like get-env or env()
• Forgetting the $env: prefix
• Trying to access variables without colon

2. Which of the following is the correct syntax to set an environment variable named MY_VAR to the value hello in PowerShell?

easy

A. set-env MY_VAR hello

B. $env:MY_VAR = 'hello'

C. env MY_VAR = hello

D. set $env:MY_VAR hello

Solution

1. Step 1: Recall how to assign environment variables in PowerShell

   PowerShell assigns environment variables by setting $env:VariableName to a value.

2. Step 2: Apply assignment to MY_VAR

   Use $env:MY_VAR = 'hello' to set the variable.

3. Final Answer:

   $env:MY_VAR = 'hello' -> Option B

4. Quick Check:

   Set env var = $env:VAR = value [OK]

Hint: Set env vars with $env:VAR = 'value' syntax [OK]

Common Mistakes:

• Using set-env which is not a PowerShell cmdlet
• Missing quotes around string values
• Trying to assign without $env: prefix

3. What will be the output of the following PowerShell commands?

$env:GREETING = 'Hello'
Write-Output "$env:GREETING, World!"

medium

A. Hello, World!

B. $env:GREETING, World!

C. GREETING, World!

D. Error: Variable not found

Solution

1. Step 1: Assign environment variable GREETING

   The command $env:GREETING = 'Hello' sets the environment variable GREETING to 'Hello'.

2. Step 2: Output the string with variable expansion

   The command Write-Output "$env:GREETING, World!" expands $env:GREETING to 'Hello', so the output is 'Hello, World!'.

3. Final Answer:

   Hello, World! -> Option A

4. Quick Check:

   Variable expands correctly = Hello, World! [OK]

Hint: Variables inside double quotes expand automatically in PowerShell [OK]

Common Mistakes:

• Expecting literal $env:GREETING instead of expansion
• Using single quotes which prevent expansion
• Assuming environment variables are not accessible in strings

4. You run this script but get an error:

Write-Output $envMY_VAR

What is the error and how to fix it?

medium

A. Environment variables cannot be used in Write-Output

B. Variable name is case sensitive; use $env:my_var

C. Missing colon after env; fix by using $env:MY_VAR

D. Use double quotes around variable: "$envMY_VAR"

Solution

1. Step 1: Identify syntax error in variable name

   The variable $envMY_VAR is invalid because environment variables require a colon after env, like $env:MY_VAR.

2. Step 2: Correct the syntax

   Fix the script by changing to Write-Output $env:MY_VAR to properly access the environment variable.

3. Final Answer:

   Missing colon after env; fix by using $env:MY_VAR -> Option C

4. Quick Check:

   Env vars need colon after env = $env:VAR [OK]

Hint: Always use colon after env to access variables: $env:VAR [OK]

Common Mistakes:

• Omitting colon after env
• Assuming variable names are case sensitive
• Trying to quote variable name instead of fixing syntax

5. You want to temporarily add a folder C:\Tools to the PATH environment variable for your current PowerShell session only. Which command correctly does this?

hard

A. $env:PATH = $env:PATH + ';C:\Tools'

B. setx PATH "$env:PATH;C:\Tools"

C. New-Item -Path Env:PATH -Value 'C:\Tools'

D. $env:PATH += 'C:\Tools'

Solution

1. Step 1: Understand session vs persistent environment variables

   Modifying $env:PATH directly changes it only for the current session.

2. Step 2: Append new folder to existing PATH

   Use $env:PATH = $env:PATH + ';C:\Tools' to add the folder, separating with a semicolon.

3. Final Answer:

   $env:PATH = $env:PATH + ';C:\Tools' -> Option A

4. Quick Check:

   Append with $env:PATH = $env:PATH + ';new_path' [OK]

Hint: Append with $env:PATH = $env:PATH + ';new_folder' for session only [OK]

Common Mistakes:

• Using setx which changes persistent variables, not session
• Using += without semicolon separator
• Overwriting PATH without appending