When expression as powerful switch in Kotlin - Mini Project: Build & Apply

Using When Expression as a Powerful Switch in Kotlin

📖 Scenario: You are building a simple program that tells the type of a day based on its name. This is like a calendar helper that categorizes days into weekdays or weekends.

🎯 Goal: Build a Kotlin program that uses the when expression to check the name of a day and print whether it is a weekday or weekend.

📋 What You'll Learn

Create a variable with the exact name day and assign it the string value "Monday".

Create a variable with the exact name weekendDays that holds a list of weekend day names: "Saturday" and "Sunday".

Use a when expression with the variable day to check if it is a weekend or a weekday.

Print the exact output "Monday is a Weekday" or similar for the given day.

💡 Why This Matters

🌍 Real World

This kind of day categorization is useful in calendar apps, scheduling software, or any program that needs to treat weekdays and weekends differently.

💼 Career

Understanding <code>when</code> expressions helps you write clear and concise decision-making code, a common task in software development.

1

Create the day variable

Create a variable called day and set it to the string "Monday".

Kotlin

# Create a variable called day and set it to "Monday"
# Your code here

Need a hint?

Use val day = "Monday" to create the variable.

2

Create the weekendDays list

Create a variable called weekendDays and assign it a list containing the strings "Saturday" and "Sunday".

Kotlin

val day = "Monday"
# Create a list called weekendDays with "Saturday" and "Sunday"
# Your code here

Need a hint?

Use listOf("Saturday", "Sunday") to create the list.

3

Use when expression to check the day type

Use a when expression with the variable day to check if it is in weekendDays. If yes, assign the string "Weekend" to a variable called dayType. Otherwise, assign "Weekday".

Kotlin

val day = "Monday"
val weekendDays = listOf("Saturday", "Sunday")
# Use when expression to assign dayType as "Weekend" or "Weekday"
# Your code here

Need a hint?

Use when (day) { in weekendDays -> "Weekend" else -> "Weekday" }.

4

Print the result

Print the message in the format: "Monday is a Weekday" using the variables day and dayType with a Kotlin println statement and string template.

Kotlin

val day = "Monday"
val weekendDays = listOf("Saturday", "Sunday")
val dayType = when (day) {
    in weekendDays -> "Weekend"
    else -> "Weekday"
}
# Print the message "Monday is a Weekday" using println and string template
# Your code here

Need a hint?

Use println("$day is a $dayType") to print the message.