Custom objects (PSCustomObject) in PowerShell - Mini Project: Build & Apply

Create and Use Custom Objects (PSCustomObject) in PowerShell

📖 Scenario: You work in a small company where you need to organize employee information clearly. You want to create a simple list of employees with their names and ages using PowerShell custom objects.

🎯 Goal: Build a PowerShell script that creates custom objects for employees, adds a filter condition, and then displays the filtered list.

📋 What You'll Learn

Create a list of custom objects with exact employee names and ages

Add a variable to set the minimum age for filtering

Use a loop or pipeline to filter employees older than the minimum age

Print the filtered list of employees

💡 Why This Matters

🌍 Real World

Organizing and filtering structured data like employee records is common in IT and business automation tasks.

💼 Career

Knowing how to create and manipulate custom objects in PowerShell is essential for system administrators and automation engineers to handle complex data easily.

1

Create a list of employee custom objects

Create a variable called employees that holds an array of three custom objects. Each object must have two properties: Name and Age. Use these exact entries: Name = 'Alice', Age = 28, Name = 'Bob', Age = 34, and Name = 'Charlie', Age = 22. Use [PSCustomObject] to create each object.

PowerShell

# Create the employees array with three PSCustomObject entries
# Your code here

Hint

Use @( ... ) to create an array and [PSCustomObject]@{} to create each object with properties.

2

Set a minimum age filter

Create a variable called minAge and set it to 25. This will be used to filter employees older than this age.

PowerShell

$employees = @(
    [PSCustomObject]@{Name='Alice'; Age=28},
    [PSCustomObject]@{Name='Bob'; Age=34},
    [PSCustomObject]@{Name='Charlie'; Age=22}
)
# Create minAge variable and set it to 25
# Your code here

Hint

Just create a simple variable $minAge and assign the number 25.

3

Filter employees older than the minimum age

Create a variable called filteredEmployees that contains only the employees from $employees whose Age is greater than $minAge. Use the Where-Object cmdlet with a script block that compares $_ .Age to $minAge.

PowerShell

$employees = @(
    [PSCustomObject]@{Name='Alice'; Age=28},
    [PSCustomObject]@{Name='Bob'; Age=34},
    [PSCustomObject]@{Name='Charlie'; Age=22}
)

$minAge = 25

# Filter employees older than minAge into filteredEmployees
# Your code here

Hint

Use the pipeline | and Where-Object { $_.Age -gt $minAge } to filter.

4

Display the filtered employees

Use Write-Output to print the $filteredEmployees variable so you can see the filtered list of employees.

PowerShell

$employees = @(
    [PSCustomObject]@{Name='Alice'; Age=28},
    [PSCustomObject]@{Name='Bob'; Age=34},
    [PSCustomObject]@{Name='Charlie'; Age=22}
)

$minAge = 25

$filteredEmployees = $employees | Where-Object { $_.Age -gt $minAge }

# Print the filteredEmployees
# Your code here

Hint

Use Write-Output $filteredEmployees to show the filtered list.

Practice

1. What is the main purpose of using [PSCustomObject] in PowerShell?

easy

A. To convert strings into numbers

B. To create objects with named properties for organizing related data

C. To create arrays of numbers automatically

D. To run commands faster in PowerShell

Solution

1. Step 1: Understand what [PSCustomObject] does

   [PSCustomObject] creates an object with named properties to hold related data clearly.

2. Step 2: Compare options

   Only "To create objects with named properties for organizing related data" correctly describes this purpose. Other options describe unrelated tasks.

3. Final Answer:

   To create objects with named properties for organizing related data -> Option B

4. Quick Check:

   Purpose of [PSCustomObject] = Organize data [OK]

Hint: Remember: [PSCustomObject] groups data with names [OK]

Common Mistakes:

• Thinking it speeds up command execution
• Confusing with arrays or type conversion
• Assuming it creates numeric sequences

2. Which of the following is the correct syntax to create a custom object with properties Name and Age in PowerShell?

easy

A. [PSCustomObject] @{Name: 'Alice'; Age: 30}

B. @{Name='Alice', Age=30} [PSCustomObject]

C. [PSCustomObject]@{Name='Alice'; Age=30}

D. [PSCustomObject]@{Name='Alice' Age=30}

Solution

1. Step 1: Recall correct syntax for custom object creation

   The correct syntax uses [PSCustomObject]@{PropertyName='Value'; PropertyName2=Value2} with semicolons separating properties.

2. Step 2: Analyze each option

   [PSCustomObject]@{Name='Alice'; Age=30} matches the correct syntax. @{Name='Alice', Age=30} [PSCustomObject] reverses order. [PSCustomObject] @{Name: 'Alice'; Age: 30} uses colons instead of equals. [PSCustomObject]@{Name='Alice' Age=30} misses semicolon between properties.

3. Final Answer:

   [PSCustomObject]@{Name='Alice'; Age=30} -> Option C

4. Quick Check:

   Correct syntax uses semicolons and equals [OK]

Hint: Use semicolons and equals inside @{ } with [PSCustomObject] [OK]

Common Mistakes:

• Using commas instead of semicolons
• Placing [PSCustomObject] after the hashtable
• Using colons instead of equals signs

3. What will be the output of this PowerShell code?

$person = [PSCustomObject]@{Name='Bob'; Age=25}; $person.Name

medium

A. Bob

B. 25

C. @{Name='Bob'; Age=25}

D. Name

Solution

1. Step 1: Understand object creation and property access

   The variable $person holds a custom object with properties Name and Age. Accessing $person.Name returns the value of the Name property.

2. Step 2: Determine the output

   The Name property was set to 'Bob', so the output is 'Bob'.

3. Final Answer:

   Bob -> Option A

4. Quick Check:

   Access property returns its value [OK]

Hint: Access properties with dot notation to get their values [OK]

Common Mistakes:

• Expecting the whole object printed
• Confusing property name with value
• Using wrong property name

4. Identify the error in this PowerShell code:

$obj = [PSCustomObject]@{Name='Eve' Age=28}

medium

A. Missing semicolon between properties inside the hashtable

B. Incorrect use of square brackets around PSCustomObject

C. Property names must be in double quotes

D. Cannot assign numbers as property values

Solution

1. Step 1: Check hashtable property separators

   Properties inside the hashtable must be separated by semicolons. Here, Name='Eve' and Age=28 are missing a semicolon between them.

2. Step 2: Verify other syntax elements

   Square brackets around PSCustomObject are correct. Property names do not require quotes. Numbers can be property values.

3. Final Answer:

   Missing semicolon between properties inside the hashtable -> Option A

4. Quick Check:

   Separate properties with semicolons [OK]

Hint: Separate each property with a semicolon inside @{ } [OK]

Common Mistakes:

• Using commas instead of semicolons
• Adding quotes around property names unnecessarily
• Thinking numbers can't be property values

5. You want to create a list of custom objects representing books with properties Title and Author. Which PowerShell code correctly creates an array of two such objects?

hard

A. [PSCustomObject]@{Title='1984', Author='Orwell'; Title='Dune', Author='Herbert'}

B. [PSCustomObject]@{Title='1984', Author='Orwell'}, [PSCustomObject]@{Title='Dune'; Author='Herbert'}

C. @{Title='1984'; Author='Orwell'}, @{Title='Dune'; Author='Herbert'}

D. @([PSCustomObject]@{Title='1984'; Author='Orwell'}, [PSCustomObject]@{Title='Dune'; Author='Herbert'})

Solution

1. Step 1: Understand how to create multiple custom objects in an array

   Each book must be a separate [PSCustomObject]. To create an array, wrap the objects in @( ) and separate them with commas.

2. Step 2: Analyze each option

   @([PSCustomObject]@{Title='1984'; Author='Orwell'}, [PSCustomObject]@{Title='Dune'; Author='Herbert'}) correctly creates two separate custom objects inside an array. [PSCustomObject]@{Title='1984', Author='Orwell'}, [PSCustomObject]@{Title='Dune'; Author='Herbert'} uses comma instead of semicolon in the first hashtable, causing a syntax error. @{Title='1984'; Author='Orwell'}, @{Title='Dune'; Author='Herbert'} creates hashtables, not custom objects. [PSCustomObject]@{Title='1984', Author='Orwell'; Title='Dune', Author='Herbert'} tries to combine two books in one object incorrectly.

3. Final Answer:

   @([PSCustomObject]@{Title='1984'; Author='Orwell'}, [PSCustomObject]@{Title='Dune'; Author='Herbert'}) -> Option D

4. Quick Check:

   Use array @( ) with separate custom objects [OK]

Hint: Wrap multiple [PSCustomObject]s in @( ) separated by commas [OK]

Common Mistakes:

• Using commas instead of semicolons inside hashtables
• Using hashtables instead of custom objects
• Combining multiple items in one object incorrectly