Swift 使用了 Codable，但类型不正确

Question

我知道 Codable = Decodable & Encodable 但是当从 xcode、

调用 json 时

Codable 是作为一个结构体给出的，但是一个错误说

Argument type'login.Type' does not conform to expected type'Encodable'出现。

json代码

struct login: Codable {
    var userId: String?
    var userPw: String?

class func LoginBoard(_ completeHandler: @escaping (login) -> Void) {
            
    let loginboard: String = MAIN_URL + "/member/login"
    guard let url = URL(string: loginboard) else {
      print("Error: cannot create URL")
        return
    }
    var urlRequest = URLRequest(url: url)
    urlRequest.httpMethod = "POST"
    urlRequest.addValue("application/json", forHTTPHeaderField: "Content-Type")
    urlRequest.addValue("application/json", forHTTPHeaderField: "Accept")
    urlRequest.httpBody = try? JSONEncoder().encode(login) // ERROR [Argument type 'login.Type' does not conform to expected type 'Encodable']
            
    let session = URLSession.shared

    let task = session.dataTask(with: urlRequest) { (data, response, error) in
        guard error == nil else {
        print("error calling Post on /todos/1")
         print(error!)
           return
        }

        guard let responseData = data else {
        print("Error: did not receive data")
          return
        }

        do {
            let decoder = JSONDecoder.init()
            let LoginList = try decoder.decode(login.self, from: responseData)
            completeHandler(LoginList)
        }
        catch {
            print("error trying to convert data to JSON")
            return
        }
    }
    task.resume()
}

没有错误试试decoder.decode

但只能在urlRequest.httpBody=试试？ JSONEncoder().encode(login) 有什么问题？

Answer 1

您需要像这样设置值。

let loginvalues = login(userId: "john", userPw: "adfadfa")

urlRequest.httpBody = try? JSONEncoder().encode(loginvalues)

如果你把它放在游乐场里，[=17=] 你会看到你得到了 json 数据。

struct Login: Codable {
    var userId: String?
    var userPw: String?
}

let loginvalues = Login(userId: "john", userPw: "adfadfa")

let test = try? JSONEncoder().encode(loginvalues)
print(String(data: test!, encoding: .utf8)!)

Swift 使用了 Codable，但类型不正确

Swift used Codable, but the type is not correct

swift

codable

jsonencoder

jsondecoder