Parse JSON data with Swift, AlamoFire and SwiftyJSON - ios

Question

As a Swift newcomer, I am very confused about how to parse some JSON data obtained from an API. I am able to get the JSON data from the api using an alamofire request. At this point, I think I have an NSDictionary object, JSON as print(JSON) logs to console a good deal of JSON.
if let result = response.result.value {
let JSON = result as! NSDictionary
print("this is what JSON is")
print(JSON)
My question is, first, is JSON in fact an NSDictionary. Second, how would I access a value in the JSON. Do I need to first convert this to a data object. Or how do I get at the nested data.
For example, let's say the JSON looks like this:
{
"contact": {
"first": "Bob",
"second":"Jones"
}
}
I came across this code on SO:
let data = JSON(data: JSON)
print("data\(data["contact"]["first"])")
But it throws an error. I have swiftyJSON installed but happy for solution with or without it.
Thanks in advance for any suggestions

Answer 1

Can you try
if let result = response.result.value as? [String:Any] {
if let contact = result["contact"] as? [String:Any] {
if let first = contact["first"] as? String {
print(first)
}
}
}
also this
let data = JSON(data: JSON)
gives error because parameter should be of type Data not Dictionary
I would prefer to return Data from Alamofire request and use Decodable to parse it and convert to required model

Answer 2

TRY THIS!
if let data = response.data {
let jsonData = JSON(data: data)
print("data : \(jsonData["contact"]["first"].string)")
}

Answer 3

Swift4 introduce amazing Codable protocol.
Using Codable, we can model JSONObject or PropertyList file into equivalent Struct or Classes by writing very few lines of code.
There are many online tool available which creates model class from you JSON
(http://www.json4swift.com/)
Example
let decoder = JSONDecoder()
let parsedObject = try decoder.decode(Class.self, from: data)
You can find detail at below link:
https://developer.apple.com/documentation/foundation/archives_and_serialization/encoding_and_decoding_custom_types