What is the way of extracting last word in a String in Swift? So if I have "Lorem ipsum dolor sit amet", return "amet". What is the most efficient way of doing this?
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7 Answers
You can use String method enumerateSubstringsInRange. First parameter just pass your string Range<Index>, and the option .byWords. Just append each substring to the resulting collection and return it.
Swift 5 or later (for older Swift syntax check edit history)
import Foundation extension StringProtocol { // for Swift 4 you need to add the constrain `where Index == String.Index` var byWords: [SubSequence] { var byWords: [SubSequence] = [] enumerateSubstrings(in: startIndex..., options: .byWords) { _, range, _, _ in byWords.append(self[range]) } return byWords } } Usage:
let sentence = "Out of this world!!!" let words = sentence.byWords // ["Out", "of", "this", "world"] let firstWord = words.first // "Out" let lastWord = words.last // world" let first2Words = words.prefix(2) // ["Out", "of"] let last2Words = words.suffix(2) // ["this", "world"] Without import Foundation
Cleaning punctuation characters filtering the letters and spaces of the string
let clean = sentence.filter{ $0.isLetter || $0.isWhitespace } find the index after the index of the last space in a string
if let lastIndex = clean.lastIndex(of: " "), let index = clean.index(lastIndex, offsetBy: 1, limitedBy: clean.index(before: clean.endIndex)) { let lastWord = clean[index...] print(lastWord) // "world" } find the index of the first space in a string
if let index = clean.firstIndex(of: " ") { let firstWord = clean[...index] print(firstWord) // "Out"" } 3 Comments
Duncan C
Nice, although I'd be hesitant to have an extension that promotes a computed property with at least
O(n) performance. I'd be more inclined to make it a function, since that makes it clear that it's doing work every time you call it.
Leo Dabus
@DuncanC Thanks but I did already here stackoverflow.com/a/39667966/2303865 You can remove the computed properties and use the method only
components(separated: .byWords)Leo Dabus
@UtkuDalmaz There is no word that starts with
"#". Btw it does return the last word "world" without the hashtagThe other answers are fine if you want to include Foundation classes. If you want to use Swift-only classes then you can do it this way:
One way to do it is to use indices. This is probably the fastest way with long strings:
Swift 4:
let str = "Lorem ipsum dolor sit amet" let size = str.reversed().firstIndex(of: " ") ?? str.count let startWord = str.index(str.endIndex, offsetBy: -size) let last = str[startWord...] // -> "amet" Or you could split the string:
Swift 4:
let str = "Lorem ipsum dolor sit amet" let split = str.split(separator: " ") let last = String(split.suffix(1).joined(separator: [" "])) let lastTwo = String(split.suffix(2).joined(separator: [" "])) print(last) // -> "amet" print(lastTwo) // -> "sit amet” Swift 3:
let str = "Lorem ipsum dolor sit amet" let split = str.characters.split(separator: " ") let last = String(split.suffix(1).joined(separator: [" "])) let lastTwo = String(split.suffix(2).joined(separator: [" "])) print(last) // -> "amet" print(lastTwo) // -> "sit amet” Swift 2:
let str = "Lorem ipsum dolor sit amet" let split = str.characters.split(Character(" ")) let last = String(split.suffix(1).joinWithSeparator([" "])) let lastTwo = String(split.suffix(2).joinWithSeparator([" "])) print(last) // -> "amet" print(lastTwo) // -> "sit amet" 2 Comments
Lucas Chwe
nice solution but a word can be separated by a comma or punctuation mark too
I would also consider using componentsSeparatedByCharactersInSet, and using the whitespace character set:
let string = "Lorem ipsum dolor sit amet" let stringArray = string.componentsSeparatedByCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet()) print(stringArray.last) 
3 Comments
senty
I like your approach! Thanks a lot! Is it possible to get the last two words with this approach or should I use a for loop?
Are you sure? You might have imported it somewhere.
String doesn't have the method componentsSeparatedByCharactersInSet. That method is part of NSString.First use componentsSeparatedByString to split your string into an array by space, then get the last word of the array using .last
var string = "Lorem ipsum dolor sit amet" var stringArr = string.componentsSeparatedByString(" ") var lastWord = stringArr.last //amet 
1 Comment
Eduard Kanevsky
For Swift 4, swift 5 and upper: .components(separatedBy: " ")
Swift 5
extension String { func trim(_ emptyToNil: Bool = true)->String? { let text = self.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines) return emptyToNil && text.isEmpty ? nil : text } var lastWord: String? { if let size = self.lastIndex(of: " "), size >= self.startIndex { return String(self[size...]).trim() } return nil } } Usage
print("Out of this world!!!".lastWord ?? "") // world!!! 
Comments
The same solution by '@Leo Dabus' but without slices: (Swift 4.x)
let fullName = "Williams Diaz Robert" let words = fullName.components(separatedBy: " ") if(words.count < 2) { return } let fistName = String(words.last ?? "") //Robert let lastNameArray = words.prefix(words.count - 1) //["Williams","Diaz"]: [String] let lastName = lastNameArray.joined(separator: " ") // "Williams Diaz" 
Comments
let value = "Hello, I am a String" let stringArray = value.components(separatedBy: .whitespaces) let lastWord = stringArray.last ?? "" print(lastWord) 