Create an Array in Swift from an NSData Object

Question

I\'m trying to store an array of integers to disk in swift. I can get them into an NSData object to store, but getting them back out into an array is difficult. I can get

Answer 1

Here is a generic way to do it.

import Foundation

extension Data {
    func elements  () -> [T] {
        return withUnsafeBytes {
            Array(UnsafeBufferPointer(start: $0, count: count/MemoryLayout.size))
        }
    }
}

let array = [1, 2, 3]
let data = Data(buffer: UnsafeBufferPointer(start: array, count: array.count))
let array2: [Int] = data.elements()

array == array2
// IN THE PLAYGROUND, THIS SHOWS AS TRUE

You must specify the type in the array2 line. Otherwise, the compiler cannot guess.