Convert Swift string to array

Question

It is even easier in Swift:

let string : String = "Hello 🐶🐮 🇩🇪"
let characters = Array(string)
println(characters)
// [H, e, l, l, o,  , 🐶, 🐮,  , 🇩🇪]

This uses the facts that

• an Array can be created from a SequenceType, and
• String conforms to the SequenceType protocol, and its sequence generator enumerates the characters.

And since Swift strings have full support for Unicode, this works even with characters outside of the "Basic Multilingual Plane" (such as 🐶) and with extended grapheme clusters (such as 🇩🇪, which is actually composed of two Unicode scalars).

---

Update: As of Swift 2, String does no longer conform to SequenceType, but the characters property provides a sequence of the Unicode characters:

let string = "Hello 🐶🐮 🇩🇪"
let characters = Array(string.characters)
print(characters)

This works in Swift 3 as well.

---

Update: As of Swift 4, String is (again) a collection of its Characters:

let string = "Hello 🐶🐮 🇩🇪"
let characters = Array(string)
print(characters)
// ["H", "e", "l", "l", "o", " ", "🐶", "🐮", " ", "🇩🇪"]

Edit (Swift 4)

In Swift 4, you don't have to use characters to use map(). Just do map() on String.

let letters = "ABC".map { String($0) }
print(letters) // ["A", "B", "C"]
print(type(of: letters)) // Array<String>

Or if you'd prefer shorter: "ABC".map(String.init) (2-bytes 😀)

Edit (Swift 2 & Swift 3)

In Swift 2 and Swift 3, You can use map() function to characters property.

let letters = "ABC".characters.map { String($0) }
print(letters) // ["A", "B", "C"]

Original (Swift 1.x)

Accepted answer doesn't seem to be the best, because sequence-converted String is not a String sequence, but Character:

$ swift
Welcome to Swift!  Type :help for assistance.
  1> Array("ABC")
$R0: [Character] = 3 values {
  [0] = "A"
  [1] = "B"
  [2] = "C"
}

This below works for me:

let str = "ABC"
let arr = map(str) { s -> String in String(s) }

Reference for a global function map() is here: http://swifter.natecook.com/func/map/

There is also this useful function on String: components(separatedBy: String)

let string = "1;2;3"
let array = string.components(separatedBy: ";")
print(array) // returns ["1", "2", "3"]

Works well to deal with strings separated by a character like ";" or even "\n"

Updated for Swift 4

Here are 3 ways.

//array of Characters
let charArr1 = [Character](myString)

//array of String.element
let charArr2 = Array(myString)

for char in myString {
  //char is of type Character
}

In some cases, what people really want is a way to convert a string into an array of little strings with 1 character length each. Here is a super efficient way to do that:

//array of String
var strArr = myString.map { String($0)}

Swift 3

Here are 3 ways.

let charArr1 = [Character](myString.characters)
let charArr2 = Array(myString.characters)
for char in myString.characters {
  //char is of type Character
}

In some cases, what people really want is a way to convert a string into an array of little strings with 1 character length each. Here is a super efficient way to do that:

var strArr = myString.characters.map { String($0)}

Or you can add an extension to String.

extension String {
   func letterize() -> [Character] {
     return Array(self.characters)
  }
}

Then you can call it like this:

let charArr = "Cat".letterize()