FREE: Watch my new YouTube videos, Xcode in 20 Seconds! >>

How to use the forEach method to loop over an array

Paul Hudson       @twostraws

In Swift we normally loop over arrays like this:

let numbers = [1, 2, 3, 4, 5]

for number in numbers {
    print(number)
}

However, Swift provides us an alternative: a dedicated array method called forEach(), that loops over each item in the array and does something with it. For example, the above loop would be written like this:

numbers.forEach {
    print($0)
}

The difference is that forEach() can’t skip over any items – you can’t exit the loop part way, without processing the rest of the items. This helps people reading your code to figure out your intent: you want to act on all items, and won’t stop in the middle.

Sponsored You’re already busy updating your app for Swift 4.2 and iOS 12, so why not let Instabug help you find and fix bugs? Add just two lines of code to your project and receive comprehensive reports with all the feedback you need to ship a world-class app – click here to learn more!

Available from iOS 8.0 – learn more in my book Pro Swift

Did this solution work for you? Please pass it on!

Other people are reading…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

Test your Swift today

Think you know Swift? My book Swift Coding Challenges will put your Swift skills to the test – it's perfect for job interviews and more!

MASTER SWIFT NOW
Buy Testing Swift Buy Practical iOS 12 Buy Pro Swift Buy Swift Design Patterns Buy Swift Coding Challenges Buy Server-Side Swift (Vapor Edition) Buy Server-Side Swift (Kitura Edition) Buy Hacking with macOS Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with Swift Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let me know!

Click here to visit the Hacking with Swift store >>