How do I convert a Swift Array to a String?

If the array contains strings, you can use the String's join method:

var array = ["1", "2", "3"]

let stringRepresentation = "-".join(array) // "1-2-3"

In Swift 2:

var array = ["1", "2", "3"]

let stringRepresentation = array.joinWithSeparator("-") // "1-2-3"

This can be useful if you want to use a specific separator (hypen, blank, comma, etc).

Otherwise you can simply use the description property, which returns a string representation of the array:

let stringRepresentation = [1, 2, 3].description // "[1, 2, 3]"

Hint: any object implementing the Printable protocol has a description property. If you adopt that protocol in your own classes/structs, you make them print friendly as well

In Swift 3

• join becomes joined, example [nil, "1", "2"].flatMap({$0}).joined()
• joinWithSeparator becomes joined(separator:) (only available to Array of Strings)

In Swift 4

var array = ["1", "2", "3"]
array.joined(separator:"-")

With Swift 5, according to your needs, you may choose one of the following Playground sample codes in order to solve your problem.

Turning an array of Characters into a String with no separator:

let characterArray: [Character] = ["J", "o", "h", "n"]
let string = String(characterArray)

print(string)
// prints "John"

Turning an array of Strings into a String with no separator:

let stringArray = ["Bob", "Dan", "Bryan"]
let string = stringArray.joined(separator: "")

print(string) // prints: "BobDanBryan"

Turning an array of Strings into a String with a separator between words:

let stringArray = ["Bob", "Dan", "Bryan"]
let string = stringArray.joined(separator: " ")

print(string) // prints: "Bob Dan Bryan"

Turning an array of Strings into a String with a separator between characters:

let stringArray = ["car", "bike", "boat"]
let characterArray = stringArray.flatMap { $0 }
let stringArray2 = characterArray.map { String($0) }
let string = stringArray2.joined(separator: ", ")

print(string) // prints: "c, a, r, b, i, k, e, b, o, a, t"

Turning an array of Floats into a String with a separator between numbers:

let floatArray = [12, 14.6, 35]
let stringArray = floatArray.map { String($0) }
let string = stringArray.joined(separator: "-")

print(string)
// prints "12.0-14.6-35.0"

Swift 2.0 Xcode 7.0 beta 6 onwards uses joinWithSeparator() instead of join():

var array = ["1", "2", "3"]
let stringRepresentation = array.joinWithSeparator("-") // "1-2-3"

joinWithSeparator is defined as an extension on SequenceType

extension SequenceType where Generator.Element == String {
    /// Interpose the `separator` between elements of `self`, then concatenate
    /// the result.  For example:
    ///
    ///     ["foo", "bar", "baz"].joinWithSeparator("-|-") // "foo-|-bar-|-baz"
    @warn_unused_result
    public func joinWithSeparator(separator: String) -> String
}

Swift 3

["I Love","Swift"].joined(separator:" ") // previously joinWithSeparator(" ")