converting Array of dictionaries into array of objects

Question

i have a string of this form:

[{"LocationsItems":[{"ItemId":4,"LocationId":3,"Qty":34},{"ItemId":19,"LocationId":3,"Qty":55}]}];

i need to convert this to an array of object, i tried this:

let data = convertedData.data(using: .utf8)!
        do {
            if let jsonArray = try JSONSerialization.jsonObject(with: data, options : .allowFragments) as? [Dictionary<String,Any>]
            {
                print(jsonArray)

            } else {
                print("bad json")
            }
        } catch let error as NSError {
            print(error)
        }
    }

and returned this , which is an array of dictionaries:

[["LocationsItems": <__NSArrayI 0x600003a1c100>(
{
    ItemId = 4;
    LocationId = 3;
    Qty = 34;
},
{
    ItemId = 19;
    LocationId = 3;
    Qty = 55;
}
)
]]

how can i extract the objects from it? thanks

Possible duplicate of [How to parse a JSON file in swift?](https://stackoverflow.com/questions/24013410/how-to-parse-a-json-file-in-swift) — Prashant Tukadiya, Oct 23 '18 at 07:22
MrJ why you want to convert, tell us the purpose of conversion? — Harjot Singh, Oct 23 '18 at 07:37
I suggest you to don't use array dictionary. Use struct or class with codable your answer is you just have to write one line `if let objects = jsonArray["LocationsItems"] as? [[String:Any]]` — Prashant Tukadiya, Oct 23 '18 at 07:45
I've updated the response, it conforms yo tour structure now @MrJ, it should work now — Durdu, Oct 23 '18 at 08:27

score 2 · Answer 1 · edited Oct 23 '18 at 08:47

2

You can create a struct of LocationItem.

struct LocationItem {
    var itemId: Int?
    var locationId: Int?
    var qty: Int?    
}

var innerDictionary = jsonArray[0] as? [String: Any]
var arrayOfDict = innerDictionary["LocationsItems"] as? [[String: Any]]

var locationsItems = arrayOfDict.map { 
    LocationItem(itemId: $0["ItemId"], locationId: $0["LocationId"], qty: $0["Qty"]) 
}

Alternatively, you can use Codable:

struct LocationItem: Codable {
    var itemId: Int?
    var locationId: Int?
    var qty: Int?

    enum CodingKeys: String, CodingKey {
        case itemId = "ItemId"
        case locationId = "LocationId"
        case qty = "Qty"
    }
}

let decoder = JSONDecoder()

do {
    let responseStructure = try decoder.decode([[String:[[String:Any]]]], from: data)
} catch {
    // failed
}

let locationItems = responseStructure[0]["LocationsItems"]

edited Oct 23 '18 at 08:47

George

25,988
10
79
133

answered Oct 23 '18 at 07:38

Durdu

4,649
2
27
47

Are you using Codeable or not? – Joakim Danielson Oct 23 '18 at 07:45
then, I guess it's ok if you use the 1st option provided – Durdu Oct 23 '18 at 08:06
i tried it, it didnt work , it gave the following output: LocationItem(itemId: nil, locationId: nil, qty: nil)] – MrJ Oct 23 '18 at 08:06
I see now your structure better, updating the response now. – Durdu Oct 23 '18 at 08:09
@MrJ Does the arrayOfDict load? I mean does it have anything relevant after it passes the line of its declaration? – Durdu Oct 23 '18 at 08:29
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/182333/discussion-between-andrei-durnea-and-mrj). – Durdu Oct 23 '18 at 08:32
if you print innerDictionary["LocationsItems"] what does output? – Durdu Oct 23 '18 at 08:37

converting Array of dictionaries into array of objects

1 Answers1