将一个JSON数组反序列化为一个Swift的对象数组

我是新来的Swift，我无法弄清楚如何将一个JSON数组反序列化成一个Swift对象数组。 我可以反序列化一个单一的JSON用户到一个Swift用户对象罚款，但只是不知道如何做一个JSON数组的用户。

这是我的User.swift类：

class User { var id: Int var firstName: String? var lastName: String? var email: String var password: String? init (){ id = 0 email = "" } init(user: NSDictionary) { id = (user["id"] as? Int)! email = (user["email"] as? String)! if let firstName = user["first_name"] { self.firstName = firstName as? String } if let lastName = user["last_name"] { self.lastName = lastName as? String } if let password = user["password"] { self.password = password as? String } } } 

这里是我试图反序列化JSON的类：

 //single user works. Alamofire.request(.GET, muURL/user) .responseJSON { response in if let user = response.result.value { var swiftUser = User(user: user as! NSDictionary) } } //array of users -- not sure how to do it. Do I need to loop? Alamofire.request(.GET, muURL/users) .responseJSON { response in if let users = response.result.value { var swiftUsers = //how to get [swiftUsers]? } } 

Answer 1

最好的方法是使用Alamofire提供的通用响应对象序列化 ，这里是一个例子：

1）将扩展添加到您的APIpipe理器或单独的文件中

  public protocol ResponseObjectSerializable { init?(response: NSHTTPURLResponse, representation: AnyObject) } extension Request { public func responseObject<T: ResponseObjectSerializable>(completionHandler: Response<T, NSError> -> Void) -> Self { let responseSerializer = ResponseSerializer<T, NSError> { request, response, data, error in guard error == nil else { return .Failure(error!) } let JSONResponseSerializer = Request.JSONResponseSerializer(options: .AllowFragments) let result = JSONResponseSerializer.serializeResponse(request, response, data, error) switch result { case .Success(let value): if let response = response, responseObject = T(response: response, representation: value) { return .Success(responseObject) } else { let failureReason = "JSON could not be serialized into response object: \(value)" let error = Error.errorWithCode(.JSONSerializationFailed, failureReason: failureReason) return .Failure(error) } case .Failure(let error): return .Failure(error) } } return response(responseSerializer: responseSerializer, completionHandler: completionHandler) } } public protocol ResponseCollectionSerializable { static func collection(response response: NSHTTPURLResponse, representation: AnyObject) -> [Self] } extension Alamofire.Request { public func responseCollection<T: ResponseCollectionSerializable>(completionHandler: Response<[T], NSError> -> Void) -> Self { let responseSerializer = ResponseSerializer<[T], NSError> { request, response, data, error in guard error == nil else { return .Failure(error!) } let JSONSerializer = Request.JSONResponseSerializer(options: .AllowFragments) let result = JSONSerializer.serializeResponse(request, response, data, error) switch result { case .Success(let value): if let response = response { return .Success(T.collection(response: response, representation: value)) } else { let failureReason = "Response collection could not be serialized due to nil response" let error = Error.errorWithCode(.JSONSerializationFailed, failureReason: failureReason) return .Failure(error) } case .Failure(let error): return .Failure(error) } } return response(responseSerializer: responseSerializer, completionHandler: completionHandler) } } 

2）像这样更新你的模型对象：

 final class User: ResponseObjectSerializable, ResponseCollectionSerializable { let username: String let name: String init?(response: NSHTTPURLResponse, representation: AnyObject) { self.username = response.URL!.lastPathComponent! self.name = representation.valueForKeyPath("name") as! String } static func collection(response response: NSHTTPURLResponse, representation: AnyObject) -> [User] { var users: [User] = [] if let representation = representation as? [[String: AnyObject]] { for userRepresentation in representation { if let user = User(response: response, representation: userRepresentation) { users.append(user) } } } return users } } 

3）那么你可以这样使用它：

 Alamofire.request(.GET, "http://example.com/users") .responseCollection { (response: Response<[User], NSError>) in debugPrint(response) } 

来源： 通用响应对象序列化

有用的链接： Alamofire JSON对象和集合的序列化

Answer 2

既然你使用Alamofire来提出你的请求，为什么不给Hearst-DD ObjectMapper一个机会，它有一个Alamofire扩展AlamofireObjectMapper 。 我想这会节省你的时间！

Answer 3

我会循环他们，然后将每个用户添加到一个数组（最好是VC的属性，而不是一个实例variables），但这里是一个例子。

  Alamofire.request(.GET, "YourURL/users") .responseJSON { response in if let users = response.result.value { for user in users { var swiftUser = User(user: user as! NSDictionary) //should ideally be a property of the VC var userArray : [User] userArray.append(swiftUser) } } } 

Answer 4

您也可以尝试EVReflection https://github.com/evermeer/EVReflection它更简单，即parsingJSON（EVReflection链接采取的代码片段）：

 let json:String = "{ \"id\": 24, \"name\": \"Bob Jefferson\", \"friends\": [{ \"id\": 29, \"name\": \"Jen Jackson\"}]}" 

你可以使用这个类：

 class User: EVObject { var id: Int = 0 var name: String = "" var friends: [User]? = [] } 

通过这种方式：

 let user = User(json: json)