Swift converting Byte Array into String

Question

I can't convert this below byte array into String in swift.

let chars: [UInt8] =  [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 0, 0]

let datastring = NSString(data: chars, encoding: NSUTF8StringEncoding)

But in android it just works fine I don't know whats wrong in swift.

Sorry its typo mistake.. now I updated the question – nik Feb 25 '16 at 07:07 — nik, Feb 25 '16 at 07:07
Do you get any errors? Is that really UTF-8? – Thilo Feb 25 '16 at 07:20 — Thilo, Feb 25 '16 at 07:20
Which version of Swift are you using? – ljk321 Feb 25 '16 at 07:43 — ljk321, Feb 25 '16 at 07:43

vadian · Accepted Answer · 2021-04-30T19:15:30.110

[UInt8] is not NSData, so you can't use the NSString(data... initializer

You might use

let chars: [UInt8] =  [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 0]
let count = chars.count / sizeof(UInt8)
let datastring = NSString(bytes: chars, length: count, encoding: NSASCIIStringEncoding)

In Swift 3 things have become much easier as a native String can be initialized with a sequence of bytes.

let datastring = String(bytes: chars, encoding: .utf8)

However the example is not meaningful because it doesn’t represent a string so datastring will be nil. Use valid data like

let chars : [UInt8] = [72, 101, 108, 108, 111]
let datastring = String(bytes: chars, encoding: .utf8) // "Hello"

score 4 · Answer 2 · answered May 10 '17 at 10:38

4

In Swift 3 you can use this:

import Foundation
let chars: [UInt8] =  [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 0, 0, 0, 0]
let string = String(data: Data(chars), encoding: .utf8)

answered May 10 '17 at 10:38

Kacper Dziubek

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5

Simpler: `String(bytes: chars, encoding: .utf8)` – Martin R May 10 '17 at 14:24
@MartinR Thanks for your answer. You should consider adding it on your own. – Sankar Jan 11 '18 at 14:43
3

Its giving string as nil. Can you tell me why?? – Shubham Agarwal Bhewanewala Jan 25 '19 at 05:43
getting nil string. Is there any other solution? – Kiran Patil Nov 27 '20 at 10:34
getting nil string as well. – Yanay Hollander Sep 01 '22 at 10:52

score 0 · Answer 3 · answered Jul 10 '21 at 13:32

0

let str = String(decoding: chars, as: UTF8.self) - changes wrong byts by 0xfffd let str = chars.map { String(UnicodeScalar($0)) }.joined()

answered Jul 10 '21 at 13:32

Oleg Drobyshev

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Swift converting Byte Array into String

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