swift - 如何在swift中创建一个空对象

Question

如何在 swift 中初始化一个空对象？这就是我所拥有的，但它也需要参数

var userInfo:User = User()

init(email: String, isVerified: String, profileImageURL: String, reputation: String, twitterHandle: String, userName: String) {
        self._email = email
        self._isVerified = isVerified
        self._profileImageURL = profileImageURL
        self._reputation = reputation
        self._twitterHandle = twitterHandle
        self._userName = userName
    }

Answer 1

像这样创建具有可选属性的类/结构

struct Employee {//struct or class
    var name: String?
    var number: String?
    var position: String?
}

然后你可以创建一个没有任何值的对象，有一些值

let emp = Employee()
let emp = Employee(name: nil, number: nil, position: nil)
let emp = Employee(name: "abc", number: nil, position: "xyz")

通过创建具有默认值的 init 方法，可以在创建对象时忽略参数

struct Employee {
    var name: String?
    var number: String?
    var position: String?
    init(name: String? = nil, number: String? = nil, position: String? = nil) {
        self.name = name
        self.number = number
        self.position = position
    }
}
let emp = Employee()
let emp = Employee(name: "abc", number: "124", position: "xyz")
let emp = Employee(name: "abc", position: "xyz")
let emp = Employee(number: "124")
let emp = Employee(name: "abc", number: "124")