Get String from NSMutableString in swift

Question

What's the proper way of getting a String from a NSMutableString? I am currently using:

var mutableString = NSMutableString(string: string)
var string = mutableString.substring(from: 0)

which seems a bit hackish...

Thanks

Answer 1

Just cast the NSMutableString as String:

var mutableString = NSMutableString(string: "Example")
var string = String(mutableString)

Or:

var mutableString = NSMutableString(string: "Example")
var string = mutableString as String

Answer 2

As already mentioned in the comments the proper way is not to use NSMutableString at all.

Your given example

let mutableString = NSMutableString(string: "Hello World")
mutableString.replaceCharacters(in: NSRange(location: 4, length: 5), with: "XXXXX")
let swiftString = String(mutableString)

can be written in native Swift

var string = "Hello World"

let nsRange = NSRange(location: 4, length: 5)
string.replaceSubrange(Range(nsRange, in: string)!, with: "XXXXX")

Same result but the latter is more efficient.