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iOS Swift 2.0 Enumerations and Optionals Introduction to Optionals Initializing Optional Values

init?(), failable init method with dictionary as the parameter and struct has 4 members to initialise as well.

init?(), failable init method with dictionary as the parameter and struct has 4 members to initialise as well. please see my code and please instruct me how to solve this challange. In playground I was able to retrieve the value of all the stored members, but sure this is not the way things has to be done

optionals.swift
struct Book {
    let title: String
    let author: String
    let price: String?
    let pubDate: String?

    // init? (dict : [title: String : author: String, price : String? : pubDate : String? ])
    init? (dict : [ String : String ] = ["title": "kamp", "author": "arun", "price" :"thousand", "pubDate" : "tomorrow"])
    {
        self.title = dict["title"]!

        self.author = dict["author"]!
        self.price =  dict["price"]
        self.pubDate = dict["pubDate"]


    }

}
let boook = Book.init()?.title

1 Answer

Cindy Lea
PLUS
Cindy Lea
Courses Plus Student 6,485 Points

You have your init & self statements wrong:

struct Book {

    let title: String
    let author: String
    let price: String?
    let pubDate: String?
    init?(dict: [String: String]){

        guard let title = dict["title"], author = dict["author"] else {
            return nil
        }
    self.title = title
    self.author = author
    self.price = dict["price"]
    self.pubDate = dict["pubDate"]

    }
}