FREE TRIAL: Accelerate your app development career with Hacking with Swift+! >>

Arrays

Arrays are collections of values that are stored as a single value. For example, John, Paul, George, and Ringo are names, but arrays let you group them in a single value called The Beatles.

In code, we write this:

let john = "John Lennon"
let paul = "Paul McCartney"
let george = "George Harrison"
let ringo = "Ringo Starr"

let beatles = [john, paul, george, ringo]

That last line makes the array: it starts and ends with brackets, with each item in the array separated by a comma.

You can read values from an array by writing a number inside brackets. Array positions count from 0, so if you want to read “Paul McCartney” you would write this:

beatles[1]

Be careful: Swift crashes if you read an item that doesn’t exist. For example, trying to read beatles[9] is a bad idea.

Note: If you’re using type annotations, arrays are written in brackets: [String], [Int], [Double], and [Bool].

Hacking with Swift is sponsored by Essential Developer

SPONSORED Join a FREE crash course for iOS devs who want to become complete senior developers — from October 18th to 24th. Learn how to apply iOS app architecture patterns through a series of lectures and practical coding sessions.

Learn more

Sponsor Hacking with Swift and reach the world's largest Swift community!

BUY OUR BOOKS
Buy Pro Swift Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift (Vapor Edition) Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Server-Side Swift (Kitura Edition) Buy Beyond Code

Was this page useful? Let us know!

Average rating: 4.6/5

 
Unknown user

You are not logged in

Log in or create account
 

Link copied to your pasteboard.