[Solved] How to parse JSON values using Swift 4?

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Your code cannot work. According to the given JSON the root object is an array [[String: Any]] and there is no key result at all.

let json = """
[{"id":1,"class":"A","Place":{"city":"sando","state":"CA"}},{"id":1,"class":"B","Place":{"city":"jambs","state":"KA"}}]
"""

let data = Data(json.utf8)

do {
    if let json = try JSONSerialization.jsonObject(with: data) as? [[String: Any]] {
        for item in json {
            if let place = item["Place"] as? [String:String] {
                print(place["city"]!, place["state"]!)
            }
        }
    }
} catch let parseError {
    print("parsing error: \(parseError)")
    let responseString = String(data: data, encoding: .utf8)
    print("raw response: \(responseString!)")
}

It’s much more convenient to use the Decodable protocol to parse the JSON into structs

struct Response : Decodable {

    private enum  CodingKeys: String, CodingKey { case id, `class`, place = "Place" }

    let id : Int
    let `class` : String
    let place : Place
}

struct Place : Decodable {
    let city, state : String
}

...

do {
    let result = try JSONDecoder().decode([Response].self, from: data)
    for item in result {
        print(item.place.city, item.place.state)
    }
} catch { print(error) }

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solved How to parse JSON values using Swift 4?