Swift: Sort array of objects alphabetically

Question

I have this:

class Movies {
 Name:String
 Date:Int
}

and an array of [Movies]. How do I sort the array alphabetically by name? I've tried:

movieArr = movieArr.sorted{ 0ドル < 1ドル }

and

movieArr = sorted(movieArr)

but that doesn't work because I'm not accessing the name attribute of Movies.

Answer 1

In the closure you pass to sort, compare the properties you want to sort by. Like this:

movieArr.sorted { 0ドル.name < 1ドル.name }

or the following in the cases that you want to bypass cases:

movieArr.sorted { 0ドル.name.lowercased() < 1ドル.name.lowercased() }

Sidenote: Typically only types start with an uppercase letter; I'd recommend using name and date, not Name and Date.

---

Example, in a playground:

class Movie {
 let name: String
 var date: Int?
 
 init(_ name: String) {
 self.name = name
 }
}
var movieA = Movie("A")
var movieB = Movie("B")
var movieC = Movie("C")
let movies = [movieB, movieC, movieA]
let sortedMovies = movies.sorted { 0ドル.name < 1ドル.name }
sortedMovies

sortedMovies will be in the order [movieA, movieB, movieC]

Swift5 Update

channelsArray = channelsArray.sorted { (channel1, channel2) -> Bool in
 let channelName1 = channel1.name
 let channelName2 = channel2.name
 return (channelName1.localizedCaseInsensitiveCompare(channelName2) == .orderedAscending)
}

• user2707185: use movies.sort instead of movies.sorted @Mike S
• Eric Aya: @julian-król You forgot to edit the other sorted to sort in the answer. Note: this is not a typo, sorted was correct in Swift 1 but has become sort in Swift 2.
• Julian: thanks for explanation. Improved my edit, should be fine, please take a look :)
• Matthieu Riegler: Beware, this won't work when sorting string that may or may not be capitalized. Comparing the .lowercaseString will solve this problem.
• dvp.petrov: @EricAya Note it is sorted in Swift 3 again :D .

Answer 2

With Swift 3, you can choose one of the following ways to solve your problem.

---

1. Using sorted(by:​) with a Movie class that does not conform to Comparable protocol

If your Movie class does not conform to Comparable protocol, you must specify in your closure the property on which you wish to use Array's sorted(by:​) method.

Movie class declaration:

import Foundation
class Movie: CustomStringConvertible {
 let name: String
 var date: Date
 var description: String { return name }
 init(name: String, date: Date = Date()) {
 self.name = name
 self.date = date
 }
}

Usage:

let avatarMovie = Movie(name: "Avatar")
let titanicMovie = Movie(name: "Titanic")
let piranhaMovie = Movie(name: "Piranha II: The Spawning")
let movies = [avatarMovie, titanicMovie, piranhaMovie]
let sortedMovies = movies.sorted(by: { 0ドル.name < 1ドル.name })
// let sortedMovies = movies.sorted { 0ドル.name < 1ドル.name } // also works
print(sortedMovies)
/*
prints: [Avatar, Piranha II: The Spawning, Titanic]
*/

---

2. Using sorted(by:​) with a Movie class that conforms to Comparable protocol

However, by making your Movie class conform to Comparable protocol, you can have a much concise code when you want to use Array's sorted(by:​) method.

Movie class declaration:

import Foundation
class Movie: CustomStringConvertible, Comparable {
 let name: String
 var date: Date
 var description: String { return name }
 init(name: String, date: Date = Date()) {
 self.name = name
 self.date = date
 }
 static func ==(lhs: Movie, rhs: Movie) -> Bool {
 return lhs.name == rhs.name
 }
 static func <(lhs: Movie, rhs: Movie) -> Bool {
 return lhs.name < rhs.name
 }
}

Usage:

let avatarMovie = Movie(name: "Avatar")
let titanicMovie = Movie(name: "Titanic")
let piranhaMovie = Movie(name: "Piranha II: The Spawning")
let movies = [avatarMovie, titanicMovie, piranhaMovie]
let sortedMovies = movies.sorted(by: { 0ドル < 1ドル })
// let sortedMovies = movies.sorted { 0ドル < 1ドル } // also works
// let sortedMovies = movies.sorted(by: <) // also works
print(sortedMovies)
/*
 prints: [Avatar, Piranha II: The Spawning, Titanic]
 */

---

3. Using sorted() with a Movie class that conforms to Comparable protocol

By making your Movie class conform to Comparable protocol, you can use Array's sorted() method as an alternative to sorted(by:​).

Movie class declaration:

import Foundation
class Movie: CustomStringConvertible, Comparable {
 let name: String
 var date: Date
 var description: String { return name }
 init(name: String, date: Date = Date()) {
 self.name = name
 self.date = date
 }
 static func ==(lhs: Movie, rhs: Movie) -> Bool {
 return lhs.name == rhs.name
 }
 static func <(lhs: Movie, rhs: Movie) -> Bool {
 return lhs.name < rhs.name
 }
}

Usage:

let avatarMovie = Movie(name: "Avatar")
let titanicMovie = Movie(name: "Titanic")
let piranhaMovie = Movie(name: "Piranha II: The Spawning")
let movies = [avatarMovie, titanicMovie, piranhaMovie]
let sortedMovies = movies.sorted()
print(sortedMovies)
/*
 prints: [Avatar, Piranha II: The Spawning, Titanic]
 */

• Kamaldeep singh Bhatia: Hey, Is there any diff. between 2nd and 3rd (except movies.sorted(by: <) and movies.sorted()) ?
• Imanou Petit: sorted(by:) and sorted() are two different methods. You can use array.sorted() as an alternative for array.sorted(by: <).
• Kamaldeep singh Bhatia: Yes, just asking in case of class definition do we need to change anything? I mean, can we have same class definition for both sorted(by:) and sorted() ?
• Imanou Petit: Yes, you can have the same implementation of your class/struct that, in any case, has to conform to Comparable protocol.
• Krunal Nagvadia: I have Array with customObject when i shoer in ascending order it's not shorting in proper way. "1" "14""28""31""4""42""49"

Answer 3

let sortArray = array.sorted(by: { 0ドル.name.lowercased() < 1ドル.name.lowercased() })

• Tom Tallak Solbu: adding .lowercased() worked for me after a long period of trying. I don't understand why, since all text were lowercased to begin with.
• Marwan Alqadi: when use lowercased() will change all names to lower case to sorted properly :)

Answer 4

For those using Swift 3, the equivalent method for the accepted answer is:

movieArr.sorted { 0ドル.Name < 1ドル.Name }

Answer 5

Most of these answers are wrong due to the failure to use a locale based comparison for sorting. Look at localizedStandardCompare()

Answer 6

Sorted array Swift 4.2

arrayOfRaces = arrayOfItems.sorted(by: { (0ドル["raceName"] as! String) < (1ドル["raceName"] as! String) })

Answer 7

*import Foundation
import CoreData
extension Messages {
 @nonobjc public class func fetchRequest() -> NSFetchRequest<Messages> {
 return NSFetchRequest<Messages>(entityName: "Messages")
 }
 @NSManaged public var text: String?
 @NSManaged public var date: Date?
 @NSManaged public var friends: Friends?
}
 //here arrMessage is the array you can sort this array as under bellow 
 var arrMessages = [Messages]()
 arrMessages.sort { (arrMessages1, arrMessages2) -> Bool in
 arrMessages1.date! > arrMessages2.date!
 }*