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

Bruce Röttgers
Bruce Röttgers
18,211 Points
Posted by Bruce Röttgers
Bruce Röttgers
18,211 Points

Don't understand the init? exercise

Tried it with guard and some others but it says as error that I either have to do behind the non optionals an ! or ? (self.title = dict["title"]! or self.title = dict["title"]!) Can you help me out here?

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

}

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points 
struct Book {
    let title: String
    let author: String
    let price: String?
    let pubDate: String?

    init?(dict: [String: String]) {
        guard let title = dict["title"], let author = dict["author"] else{
            return nil
        }
        self.title = title
        self.author = author
        self.price = dict["price"]
        self.pubDate = dict["pubDate"]
    }

}