Dictionary creation and access in Swift - Mini Project: Build & Apply

Dictionary creation and access

📖 Scenario: You are organizing a small library's book collection. Each book has a unique code and a title.

🎯 Goal: Create a dictionary to store book codes and titles, then access and print a specific book title using its code.

📋 What You'll Learn

Create a dictionary with exact book codes and titles

Create a variable to hold a specific book code

Access the dictionary using the book code variable

Print the accessed book title

💡 Why This Matters

🌍 Real World

Dictionaries are used to store and look up data quickly, like a phone book or a product catalog.

💼 Career

Knowing how to create and access dictionaries is essential for many programming tasks, including data handling and app development.

1

Create the book dictionary

Create a dictionary called books with these exact entries: "B001": "The Swift Programming Language", "B002": "Introduction to Algorithms", "B003": "Clean Code"

Swift

# Your code here

Need a hint?

Use square brackets to create a dictionary with key-value pairs separated by colons.

2

Set the book code variable

Create a variable called selectedCode and set it to the string "B002"

Swift

let books = ["B001": "The Swift Programming Language", "B002": "Introduction to Algorithms", "B003": "Clean Code"]
# Your code here

Need a hint?

Use let to create a constant string variable.

3

Access the book title

Create a variable called selectedBook and set it to the value from books using the key selectedCode. Use optional binding to safely unwrap the value.

Swift

let books = ["B001": "The Swift Programming Language", "B002": "Introduction to Algorithms", "B003": "Clean Code"]
let selectedCode = "B002"
# Your code here

Need a hint?

Use if let to safely get the value from the dictionary.

4

Print the selected book title

Inside the if let block, write print(selectedBook) to display the book title.

Swift

let books = ["B001": "The Swift Programming Language", "B002": "Introduction to Algorithms", "B003": "Clean Code"]
let selectedCode = "B002"
if let selectedBook = books[selectedCode] {
    # Your code here
}

Need a hint?

Use print(selectedBook) inside the if let block to show the book title.