JSON operations (ConvertFrom-Json, ConvertTo-Json) in PowerShell - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to convert a JSON string to a PowerShell object.

PowerShell

$jsonString = '{"name":"Alice","age":30}'
$obj = $jsonString | [1]

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

AConvertFrom-Json

BConvertTo-Json

COut-String

DConvertTo-Xml

Attempts:

3 left

💡 Hint

Common Mistakes

Using ConvertTo-Json instead of ConvertFrom-Json.

Trying to use Out-String which just formats output as text.

The ConvertFrom-Json cmdlet converts a JSON string into a PowerShell object.

2fill in blank

medium

Complete the code to convert a PowerShell object to a JSON string.

PowerShell

$obj = @{name='Bob'; age=25}
$jsonString = $obj | [1]

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

AOut-File

BConvertFrom-Json

CConvertTo-Json

DConvertTo-Csv

Attempts:

3 left

💡 Hint

Common Mistakes

Using ConvertFrom-Json which does the opposite conversion.

Using Out-File which writes to a file, not convert to JSON.

The ConvertTo-Json cmdlet converts a PowerShell object into a JSON string.

3fill in blank

hard

Fix the error in the code to correctly convert JSON string to object.

PowerShell

$jsonString = '{"city":"Paris","population":2140000}'
$obj = [1] $jsonString

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

AGet-Content

BConvertFrom-Json

COut-String

DConvertTo-Json

Attempts:

3 left

💡 Hint

Common Mistakes

Using ConvertTo-Json instead of ConvertFrom-Json.

Trying to use Get-Content which reads files, not convert JSON strings.

To convert JSON text to an object, use ConvertFrom-Json. Using ConvertTo-Json here is wrong.

4fill in blank

hard

Fill both blanks to create a JSON string from an object and then convert it back to an object.

PowerShell

$obj = @{fruit='Apple'; color='Red'}
$json = $obj | [1]
$newObj = $json | [2]

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

AConvertTo-Json

BConvertFrom-Json

COut-String

DGet-Content

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the cmdlets order.

Using Out-String which does not convert JSON.

First, convert the object to JSON with ConvertTo-Json. Then convert JSON back to object with ConvertFrom-Json.

5fill in blank

hard

Fill all three blanks to convert a JSON string to object, modify it, and convert back to JSON.

PowerShell

$jsonString = '{"animal":"Dog","age":5}'
$obj = $jsonString | [1]
$obj.age = $obj.age + 1
$newJson = $obj | [2]
Write-Output [3]

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

AConvertFrom-Json

BConvertTo-Json

C$newJson

D$obj

Attempts:

3 left

💡 Hint

Common Mistakes

Using ConvertTo-Json first instead of ConvertFrom-Json.

Outputting the object instead of the JSON string.

Convert JSON string to object with ConvertFrom-Json, then back to JSON with ConvertTo-Json. Finally, output the new JSON string.

Practice

1. What does the PowerShell cmdlet ConvertFrom-Json do?

easy

A. It converts JSON text into PowerShell objects.

B. It converts PowerShell objects into JSON text.

C. It formats JSON text for better readability.

D. It validates JSON syntax without conversion.

Solution

1. Step 1: Understand the purpose of ConvertFrom-Json

   This cmdlet takes JSON formatted text and turns it into PowerShell objects you can work with.

2. Step 2: Differentiate from ConvertTo-Json

   ConvertTo-Json does the opposite by turning objects into JSON text, so it is not the correct answer here.

3. Final Answer:

   It converts JSON text into PowerShell objects. -> Option A

4. Quick Check:

   ConvertFrom-Json = JSON text to objects [OK]

Hint: ConvertFrom-Json = JSON text to objects [OK]

Common Mistakes:

• Confusing ConvertFrom-Json with ConvertTo-Json
• Thinking it only formats JSON without conversion
• Assuming it validates JSON syntax only

2. Which of the following is the correct syntax to convert a JSON string stored in variable $jsonText into a PowerShell object?

easy

A. ConvertTo-Json $jsonText

B. $jsonText | ConvertTo-Json

C. ConvertFrom-Json $jsonText -Compress

D. $jsonText | ConvertFrom-Json

Solution

1. Step 1: Identify the correct cmdlet for JSON to object conversion

   ConvertFrom-Json converts JSON text to PowerShell objects, so it is the right cmdlet.

2. Step 2: Check the syntax for using pipeline

   Using $jsonText | ConvertFrom-Json is the correct way to pipe the JSON string into the cmdlet.

3. Final Answer:

   $jsonText | ConvertFrom-Json -> Option D

4. Quick Check:

   Pipe JSON string to ConvertFrom-Json [OK]

Hint: Pipe JSON string to ConvertFrom-Json for conversion [OK]

Common Mistakes:

• Using ConvertTo-Json instead of ConvertFrom-Json
• Trying to call ConvertFrom-Json without pipeline incorrectly
• Confusing parameter order or cmdlet usage

3. What is the output of this PowerShell code?

$json = '{"name":"Alice","age":30}'
$obj = $json | ConvertFrom-Json
$obj.age

medium

A. Error: Cannot convert string to object

B. 30

C. age

D. "30"

Solution

1. Step 1: Convert JSON string to object

   The JSON string contains a property "age" with value 30 (number). ConvertFrom-Json creates an object with property age = 30.

2. Step 2: Access the age property

   Accessing $obj.age returns the numeric value 30, not a string or error.

3. Final Answer:

   30 -> Option B

4. Quick Check:

   Property age value = 30 [OK]

Hint: ConvertFrom-Json creates objects; access properties directly [OK]

Common Mistakes:

• Expecting age as a string with quotes
• Thinking the output is the property name 'age'
• Assuming conversion error occurs

4. What is the output of this PowerShell code?

$json = '{"name":"Bob","age":25}'
$obj = ConvertFrom-Json $json
Write-Output $obj.name

medium

A. Bob

B. "Bob"

C. name

D. Error: Cannot convert string to object

Solution

1. Step 1: Convert JSON string to object

   The JSON string contains a property "name" with value Bob (string). ConvertFrom-Json creates an object with property name = Bob.

2. Step 2: Access the name property

   Accessing $obj.name returns the string value Bob, not a quoted string or error.

3. Final Answer:

   Bob -> Option A

4. Quick Check:

   Property name value = Bob [OK]

Hint: ConvertFrom-Json creates objects; access properties directly [OK]

Common Mistakes:

• Expecting output as a string with quotes
• Thinking the output is the property name 'name'
• Assuming positional argument causes conversion error

5. You have a PowerShell object:

$person = @{ Name = "Eve"; Age = 28; Skills = @("PowerShell", "JSON") }

Which command correctly converts this object to JSON text with indentation for readability?

hard

A. $person | ConvertTo-Json -Depth 2 -Compress

B. $person | ConvertTo-Json -Depth 2 -Pretty

C. $person | ConvertTo-Json -Depth 2

D. ConvertTo-Json $person -Depth 2 -Compress

Solution

1. Step 1: Understand ConvertTo-Json parameters

   ConvertTo-Json converts objects to JSON text. The -Depth parameter controls how deep nested objects are converted.

2. Step 2: Identify correct parameter for indentation

   By default, ConvertTo-Json outputs indented JSON. The -Compress parameter removes whitespace, so it is not desired. There is no -Pretty parameter.

3. Final Answer:

   $person | ConvertTo-Json -Depth 2 -> Option C

4. Quick Check:

   Default output is indented JSON [OK]

Hint: Use ConvertTo-Json with -Depth; default output is indented [OK]

Common Mistakes:

• Using -Compress removes indentation
• Using non-existent -Pretty parameter
• Not setting -Depth for nested objects