How to convert a character to an integer in Swift 3

Question

I am trying to simply convert a character or string to an integer in Swift 3. I am a long time C++ developer who is just learning Swift and finding it extremely frustrating to do some of the simplest things in Swift 3 (ie, indexing into a string, converting a character to an int).

Can someone please help me convert characters to ints, specifically in Swift 3 Xcode 8?

Thank you!

https://www.hackingwithswift.com/example-code/language/how-to-convert-a-string-to-an-int — Sachin Vas, Feb 16 '17 at 03:55
I don't think it is a duplicate as some casting rules have changed since Swift 2.0 — Michael Bremerkamp, Feb 16 '17 at 17:10

score 4 · Accepted Answer · edited May 28 '18 at 01:08

It's as simple as this.

let myString = "5"
let sum = 3 +  Int(myString)!  // Produces 8
print(Int(myString)!)

Indexing

let str = "My test String Index"
let index = str.index(str.startIndex, offsetBy: 4)
str[index] // Returns e from test

let endIndex = str.index(str.endIndex, offsetBy:-2)
str[Range(index ..< endIndex)] // returns String "est String Ind"

str.substring(from: index) // returns String "est String Index"
str.substring(to: index) // returns String "My t"

score 1 · Answer 2 · answered Feb 16 '17 at 04:00

1

let string = "1"
if let integer = Int(string) {
    print(integer)
}

answered Feb 16 '17 at 04:00

R0CKSTAR

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How to convert a character to an integer in Swift 3

2 Answers2