ios - 为什么我可以将结构放入操场上的数组中而不放在 View Controller 中

为什么在操场上这样做很好，但当我将其放入viewController时，它返回“viewController.type没有名为extent的成员”
这让我很生气，所以我非常感谢你的帮助！!!

class ViewController: UIViewController {

    struct TopicBook {

        var name: String
        var species: [String]
        var subject: String
        var rotation: [String]
        var unit: String
        var extra: String
        var content: String
        var level: [(Int,Int)]

        init(name: String, species: [String], subject: String, rotation: [String], unit: String, extra: String, content: String, level: [(Int,Int)]) {

            self.name = name
            self.species = species
            self.subject = subject
            self.rotation = rotation
            self.unit = unit
            self.extra = extra
            self.content = content
            self.level = level
        }
    }

    var extext = TopicBook (name: "Name" , species: ["species","species"], subject: "subject", rotation: ["rotation"], unit: "unit", extra: "extra", content: "content", level: [(1,1)])

    let sete = [extent]

最佳答案

试试这个

struct TopicBook {

    var name: String
    var species: [String]
    var subject: String
    var rotation: [String]
    var unit: String
    var extra: String
    var content: String
    var level: [(Int,Int)]

    init(name: String, species: [String], subject: String, rotation: [String], unit: String, extra: String, content: String, level: [(Int,Int)]) {

        self.name = name
        self.species = species
        self.subject = subject
        self.rotation = rotation
        self.unit = unit
        self.extra = extra
        self.content = content
        self.level = level
    }
}


class ViewController: UIViewController {
   var extent:TopicBook?
   var extent2:TopicBook?

    override func viewDidLoad() {
    super.viewDidLoad()

        extent = TopicBook (name: "Name" , species: ["species","species"], subject: "subject", rotation: ["rotation"], unit: "unit", extra: "extra", content: "content", level: [(1,1)])

        extent2 = TopicBook (name: "JustToShow" , species: ["JustToShow","JustToShow"], subject: "JustToShow", rotation: ["JustToShow"], unit: "JustToShow", extra: "JustToShow", content: "JustToShow", level: [(2,2)])


    }

  override func viewDidAppear(animated:Bool){
  super.viewDidAppear(true)

    //If you want it to have multiple TopicBooks inside, do this
//var seteMutable:[TopicBook] = [ ]
//seteMutable =[extent!]
//seteMutable.append(extent2!)
//let seteTrial = seteMutable

//println(seteTrial[0].name)
//println(seteTrial[1].name)

//else if you want it to have just one TopicBook inside, do this
    let sete = [extent!]
    // sete is a TopicBook array now
    //you can use sete[0]
    //Placing it inside viewDidAppear is an example, you can define "sete" in anywhere you will use it.
    //viewDidAppear gets called after viewDidLoad, this is why i put it here
    }
        }

关于ios - 为什么我可以将结构放入操场上的数组中而不放在 View Controller 中，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/31506730/