swift How to cast from Int? to String

Question

In Swift, i cant cast Int to String by:

var iString:Int = 100
var strString = String(iString)

But my variable in Int? , there for error:

Answer 1

If you need a one-liner it can be achieved by:

let x: Int? = 10
x.flatMap { String($0) } // produces "10"
let y: Int? = nil
y.flatMap { String($0) } // produces nil

if you need a default value, you can simply go with

(y.flatMap { String($0) }) ?? ""

EDIT:

Even better without curly brackets:

y.flatMap(String.init)

Apple's flatMap(_:) Documentation