How to use map() to transform an array
Swift version: 5.1
The map() method allows us to transform arrays (and indeed any kind of collection) using a transformation closure we specify. The return value will be an array of the same size, containing your transformed elements.
For example, given the following array:
let numbers = [1, 2, 3, 4]We could use map() to transform those numbers so they are doubled, like this:
let doubled = numbers.map { $0 * 2 }You can map whatever you want. For example, you could convert an array of strings to be uppercase:
let strings = ["John", "Paul", "George", "Ringo"]
let uppercased = strings.map { $0.uppercased() }SAVE 20% ON iOS CONF SG The largest iOS conference in Southeast Asia is back in Singapore for the 5th time in January 2020, now with two days of workshops plus two days of talks on SwiftUI, Combine, GraphQL, and more! Save a massive 20% on your tickets by clicking on this link.
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