How to initialize structure from json object

Question

Hi, I'm new to the quick idea. How to initialize a structure from a json object. I could not figure out how to do this.

{"user": {"name": "cruskuaka", "email": " [e-mail] ", "PHONENO": "018833455"}, "address": {"home": "100", "street" : "B", "city": {"city_id": "1", "city_name": "Galway City Center"}, "city": {"city_id": "10", "city_name": "Galway"} , "Address_id": "200", "full_address": "100, B, Galway city center, Galway"}, "delivery_instruction": "no call", "delivery_method": "1"}

Here's all the struct :

struct Contact { let user : User let address : Address let deliveryInstruction : String let deliveryMethod : String init(dictionary: [String: Any]) { self.deliveryInstruction = dictionary["delivery_instruction"] as? String ?? "" self.deliveryMethod = dictionary["delivery_method"] as? String ?? "" self.address = Address(dictionary: dictionary["address"] as? [String:Any] ?? [:]) self.user = User(dictionary: dictionary["address"] as? [String:Any] ?? [:]) } } 

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 struct User { let name : String let email : String let phoneNo : String init(dictionary : [String:Any] ) { self.name = dictionary["name"] as? String ?? "" self.email = dictionary["email"] as? String ?? "" self.phoneNo = dictionary["phoneNo"] as? String ?? "" } } 

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 struct Address { let city : City let town : Town let addressId : String let fullAddress : String let house : String let street: String init(dictionary : [String:Any] ) { self.addressId = dictionary["address_id"] as? String ?? "" self.fullAddress = dictionary["full_address"] as? String ?? "" self.house = dictionary["house"] as? String ?? "" self.street = dictionary["street"] as? String ?? "" self.city = City(dictionary: dictionary["address"] as? [String:Any] ?? [:]) self.town = Town(dictionary: dictionary["address"] as? [String:Any] ?? [:]) } } 

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 struct City { let cityId : String let cityName : String init(dictionary : [String:Any] ) { self.cityId = dictionary["city_id"] as? String ?? "" self.cityName = dictionary["city_name"] as? String ?? "" } } 

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 struct Town { let townId : String let townName : String init(dictionary : [String:Any]) { self.townId = dictionary["town_id"] as? String ?? "" self.townName = dictionary["town_name"] as? String ?? "" } } 

Answer 1

There are several errors in the code, but you are on the right track. You use the wrong key when initializing your users, city and city structures. I also created two more initializers so that you can initialize your structure with a dictionary, json string, or just your data:

 struct Contact: CustomStringConvertible { let user: User let address: Address let deliveryInstruction: String let deliveryMethod: String // customize the description to your needs var description: String { return "\(user.name) \(deliveryInstruction) \(deliveryMethod)" } init(dictionary: [String: Any]) { self.deliveryInstruction = dictionary["delivery_instruction"] as? String ?? "" self.deliveryMethod = dictionary["delivery_method"] as? String ?? "" self.address = Address(dictionary: dictionary["address"] as? [String: Any] ?? [:]) self.user = User(dictionary: dictionary["user"] as? [String: Any] ?? [:]) } init?(data: Data) { guard let json = (try? JSONSerialization.jsonObject(with: data)) as? [String: Any] else { return nil } self.init(dictionary: json) } init?(json: String) { self.init(data: Data(json.utf8)) } } 

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 struct User: CustomStringConvertible { let name: String let email: String let phone: String let description: String init(dictionary: [String: Any]) { self.name = dictionary["name"] as? String ?? "" self.email = dictionary["email"] as? String ?? "" self.phone = dictionary["phoneNo"] as? String ?? "" self.description = "name: \(name) - email: \(email) - phone: \(phone)" } } 

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 struct Address: CustomStringConvertible { let id: String let street: String let house: String let city: City let town: Town let description: String init(dictionary: [String: Any] ) { self.id = dictionary["address_id"] as? String ?? "" self.description = dictionary["full_address"] as? String ?? "" self.house = dictionary["house"] as? String ?? "" self.street = dictionary["street"] as? String ?? "" self.city = City(dictionary: dictionary["city"] as? [String: Any] ?? [:]) self.town = Town(dictionary: dictionary["town"] as? [String: Any] ?? [:]) } } 

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 struct City: CustomStringConvertible { let id: String let name: String // customize the description to your needs var description: String { return name } init(dictionary: [String: Any] ) { self.id = dictionary["city_id"] as? String ?? "" self.name = dictionary["city_name"] as? String ?? "" } } 

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 struct Town: CustomStringConvertible { let id: String let name: String // customize the description to your needs var description: String { return name } init(dictionary: [String: Any]) { self.id = dictionary["town_id"] as? String ?? "" self.name = dictionary["town_name"] as? String ?? "" } } 

Check initialization from JSON:

 let json = "{\"user\": {\"name\": \"crst\",\"email\": \" [e-mail] \",\"phoneNo\":\"018833455\"},\"address\": {\"house\": \"100\",\"street\": \"B\",\"town\":{\"town_id\": \"1\",\"town_name\": \"Galway city center\"},\"city\":{\"city_id\": \"10\",\"city_name\": \"Galway\"},\"address_id\":\"200\", \"full_address\":\"100, B, Galway city center,Galway\" },\"delivery_instruction\": \"no call\",\"delivery_method\": \"1\" }" let contact = Contact(json: json) // crst no call 1 contact // crst no call 1 contact?.user // name: crst - email: [e-mail] - phone: [phone] contact?.user.name // "crst" contact?.user.email // " [e-mail] " contact?.user.phone // "018833455" contact?.address // 100, B, Galway city center,Galway contact?.address.id // 200 contact?.address.street // B contact?.address.town // Galway city center contact?.address.city // Galway contact?.deliveryInstruction // "no call" contact?.deliveryMethod // 1