Swift 2反射错误

Question

我查看了一个 swift 代码，试图创建一个将对象序列化为 JSON 的反射函数。问题是当我调用初始化器来获取反射时它抛出了一个疯狂的错误

struct Address {
    var street: String
}

struct Person {
    var name: String = "Dre"
    var age: Int = 33
    var dutch: Bool = false
    var address: Address? = Address(street: "Clark Drive")
}

// Throws an error on the next line
let mirror = Mirror(reflecting: Person)

当我尝试将镜像的值设置为镜像初始化的结果时，出现以下错误：

Missing argument label 'reflecting:' in call

Cannot create a single-element tuple with an element label

知道这里可能出了什么问题吗？

Answer 1

您需要传递 Person 的实例而不是 class Person。例如：

struct Address {
    var street: String
}

struct Person {
    var name: String = "Dre"
    var age: Int = 33
    var dutch: Bool = false
    var address: Address? = Address(street: "Clark Drive")
}

let person = Person()
let mirror = Mirror(reflecting: person)

print(mirror.displayStyle)
for case let (label?, value) in mirror.children {
    print(label, value)
}

打印：

Optional(Struct)
name Dre
age 33
dutch false
address Optional(Address(street: "Clark Drive"))
Mirror for Bookmark

Answer 2

错误：

func jediGreet(name: String, ability: String) -> (farewell: String, mayTheForceBeWithYou: String) {
  return ("Good bye, \(name).", " May the \(ability) be with you.")
}

let retValue = jediGreet("old friend", "Force")
println(retValue)
println(retValue.farewell)
println(retValue.mayTheForceBeWithYou)

正确：

func jediGreet(name: String, ability: String) -> (farewell: String, mayTheForceBeWithYou: String) {
  return ("Good bye, \(name).", " May the \(ability) be with you.")
}

let retValue = jediGreet (name:"old friend",ability: "Force")
print(retValue)
print(retValue.farewell)
print(retValue.mayTheForceBeWithYou)

Swift 2反射错误

Swift 2 Reflection Error

reflection

mirror

swift2

xcode7.3