Map JSON data and put it into an array in Swift

Question

I have the following problem.

I use Alamofire request. The response is a JSON.

        Alamofire.request(url, method: .get).responseJSON {
        response in
        if response.result.isSuccess {

            print("Success! Got the korosztaly data")
            let koJSON : JSON = JSON(response.result.value!)


           print(koJSON)

        }
        else {
            print("Error \(String(describing: response.result.error))")
        }
    }

The result of the koJSON is the following:

{ "members": [ {"name": "Sarah"}, {"name": "David"}, {"name": "Michael"} ] }

I want to create an Members array and put all of the data into it. The result should be the following

Members = ["Sarah", "David", "Michael"]

Scriptable · Accepted Answer · 2018-02-14 14:59:48Z

3

I prefer to use the map function. It will iterate over each item in the array and allow you to pull out the selected information, or do a transformation on it.

if let resp = response.result.value as? [String: AnyObject], 
      let membersArr = resp["members"] as? [[String: String]] {
   let members = membersArr.map { $0["name"] }
}

Output should be as expected.

You can read more about map and other high order functions here

edited Feb 14, 2018 at 14:59

answered Feb 14, 2018 at 14:19

Scriptable

19.9k6 gold badges60 silver badges80 bronze badges

Sign up to request clarification or add additional context in comments.

7 Comments

janosdupai Over a year ago

"Cast from 'JSON' to unrelated type '[[String : String]]' always fails" - is the message..

janosdupai Over a year ago

"Type 'Any' has no subscript members" is the error message

Scriptable Over a year ago

I have updated the answer, try that. I think Alamofire automatically casts as String: Any

janosdupai Over a year ago

Cannot subscript a value of type '[[String : AnyObject]]' with an index of type 'String' error at your second line.

Scriptable Over a year ago

sorry my mistake, i updated again. first cast should be [String: AnyObject] not [[String: AnyObject]]

|

Collectives™ on Stack Overflow

Map JSON data and put it into an array in Swift

1 Answer 1

7 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

7 Comments

Your Answer

Sign up or log in

Post as a guest

Related