How to serialize or convert Swift objects to JSON?

In Swift 4, you can inherit from the Codable type.

struct Dog: Codable {    var name: String    var owner: String}// Encodelet dog = Dog(name: "Rex", owner: "Etgar")let jsonEncoder = JSONEncoder()let jsonData = try jsonEncoder.encode(dog)let json = String(data: jsonData, encoding: String.Encoding.utf16)// Decodelet jsonDecoder = JSONDecoder()let secondDog = try jsonDecoder.decode(Dog.self, from: jsonData)

Along with Swift 4 (Foundation) now it is natively supported in both ways, JSON string to an object - an object to JSON string. Please see Apple's documentation here JSONDecoder() and here JSONEncoder()

JSON String to Object

let jsonData = jsonString.data(using: .utf8)!let decoder = JSONDecoder()let myStruct = try! decoder.decode(myStruct.self, from: jsonData)

Swift Object to JSONString

let encoder = JSONEncoder()encoder.outputFormatting = .prettyPrintedlet data = try! encoder.encode(myStruct)print(String(data: data, encoding: .utf8)!)

You can find all details and examples here Ultimate Guide to JSON Parsing With Swift 4

UPDATE: Codable protocol introduced in Swift 4 should be sufficient for most of the JSON parsing cases. Below answer is for people who are stuck in previous versions of Swift and for legacy reasons

EVReflection :

• This works of reflection principle. This takes less code and also supports NSDictionary, NSCoding, Printable, Hashable and Equatable

Example:

    class User: EVObject { # extend EVObject method for the class       var id: Int = 0       var name: String = ""       var friends: [User]? = []    }    # use like below    let json:String = "{\"id\": 24, \"name\": \"Bob Jefferson\", \"friends\": [{\"id\": 29, \"name\": \"Jen Jackson\"}]}"    let user = User(json: json)

ObjectMapper :

• Another way is by using ObjectMapper. This gives more control but also takes a lot more code.

Example:

    class User: Mappable { # extend Mappable method for the class       var id: Int?       var name: String?       required init?(_ map: Map) {       }       func mapping(map: Map) { # write mapping code          name    <- map["name"]          id      <- map["id"]       }    }    # use like below    let json:String = "{\"id\": 24, \"name\": \"Bob Jefferson\", \"friends\": [{\"id\": 29, \"name\": \"Jen Jackson\"}]}"    let user = Mapper<User>().map(json)