Btukfyl

This code in Swift Xcode 10.1 keeps throwing a Thread 1: signal SIGABART error and I don't know why.

    let item = UserDefaults.standard.object(forKey: "To Does")

    var arrayItem:[String]

    print("about to check")

    if let arrayItem2 = item as! [String]?{



        arrayItem = arrayItem2

        arrayItem.append(textInput.text!)

        UserDefaults.standard.set(arrayItem, forKey: "To Does")

        print(arrayItem)



    }else{

        UserDefaults.standard.set(textInput.text!, forKey: "To Does")

    }

    textInput.text = ""

Never use a forced cast with if let. Never force cast to an optional. Neither make any sense.

Even once you fix that you have a problem. You first write a string to user defaults if there is nothing yet for the key. But then you try to read an array. That will never work.

Simplify your code and always write an read an array.

var items = UserDefaults.standard.array(forKey: "To Does") as? [String] ?? 

items.append(textInput.text!)

UserDefaults.standard.set(items, forKey: "To Does")

Try printing an item to console. Chances are it's neither nil, nor an [String] and it fails a forced cast.

If it's not - you can use a simpler cast. Try this in playground:

let item: Any? = 2

var arrayItem: [String] = 

print("about to check")

if let arrayItem2 = item as? [String] {



    arrayItem = arrayItem2

    arrayItem.append("foo")

    print(arrayItem)

} else {

    print("doing nothing")

}

Outputs:

about to check

doing nothing