Overriding Methods

Question

Not sure exactly how to override the method ...

Challenge Task 1 of 1

I've provided a base class Person in the editor below. Once an instance of Person is created, you can call getFullName() and get a person's full name.

Your job is to create a class named Doctor that overrides the getFullName() method. Once you have a class definition, create an instance and assign it to a constant named someDoctor.

For example, given the first name "Sam", and last name "Smith", calling getFullName() on an instance of Person would return "Sam Smith", but calling the same method on an instance of Doctor would return "Dr. Smith".

/Users/mattconway/Desktop/Screen Shot 2016-01-26 at 5.37.28 PM.png

classes.swift

class Person {
    let firstName: String
    let lastName: String

    init(firstName: String, lastName: String) {
        self.firstName = firstName
        self.lastName = lastName
    }

    func getFullName() -> String {
        return "\(firstName) \(lastName)"
    }
}

// Enter your code below
class Doctor: Person {
  override init(firstName: String) {
  self.firstName = firstName
  self.lastName = lastName
  }
}

let someDoctor = Doctor("Dr. \(lastName)")
  print(someDoctor)

Answer 1 · 2016-01-26T23:13:38Z

January 26, 2016 11:13pm

Hi Matt,

Because your subclass does not introduct any new properties that need to be initialised, there is no need for you to write an initialiser for it. It will just use the one defined by the parent class.

So that means you just need to override the getFullName method within it so tht it returns Dr. Smith rather than Sam Smith. The code would look like this.

class Doctor: Person {
    override func getFullName() -> String {
        return "Dr. \(lastName)"
    }
}

let someDoctor = Doctor(firstName: "Sam", lastName: "Smith")

So now a calling getFullName on the Doctor object would return "Dr. Smith" by using that overridden method in the subclass. :)

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Matt Conway

Matt Conway

Overriding Methods

1 Answer

Nathan Tallack

Nathan Tallack

Matt Conway

Matt Conway