NSSortDescriptor evaluating ascending numbers (Swift)

Question

App has contentid coming in as a number string from a json file:

let contentid: AnyObject! = jsonFeed[\"contentid\"]

let stream:Dictionary = [
         


        

Answer 1

In my case I tried it with

let descriptor: NSSortDescriptor = NSSortDescriptor(key: "formId", ascending: true, selector: #selector(NSString.localizedStandardCompare(_:))) Its working for me.

Answer 2

The values you want to sort are actually strings and not numbers, thus the strange sort order. For Swift there exist an initializer init(key:ascending:selector:) of NSSortDescriptorand thus you can use selector: "localizedStandardCompare:" as described for example at nshipster.com/nssortdescriptor

The localizedStandardCompare: gives you a Finder like sorting of string values in a way that numbers are sorted naturally as you would sort numbers. So 1,...,9,10,...,99, 100 etc.

Answer 3

        let descriptor: NSSortDescriptor = NSSortDescriptor(key: "message_time", ascending: true)
        let sortedResults = arrayForMessages.sortedArray(using: [descriptor])
        print(sortedResults)