Learn Swift Fundamentals by preparing for Job Interview, Questions 79 ~ 82 For OOP

These are the most basic concepts of OOP. I think most of you just know about it. But if you are a complete beginner, watch, study and prepare properly.

79) What is Base / Root class in Swift?

Answer:

• Swift has no base class as in Objective-C.
• Classes can be created without any base class / parent class. In such cases, the current class itself is the base class.
• If a class is derived from any class, then the super class is its base class.

80) What is self and super keywords?

Answer:

• self and super are keywords used in instance methods of a class.
• self refers to the current class object in which the method is present. To refer the current class properties and methods use self.
• super refers to the Parent class object of the current class. To refer its Parent class properties and methods use super.

Swift Super vs Self

81) Can we achieve Overriding without inheritance?

Answer:

• No, overriding needs at least two classes and those two must be in inheritance relationship.

82) When do you prefer struct over class?

Answer:

• In Swift, structs and classes give you value and reference-based constructs for your objects.
• struct is preferred for objects designed for data storage like Array.
• struct also helps remove memory issues when passing objects in a multi-threaded environment.
• class, unlike struct, supports inheritance and is used more for containing logic like UIViewController.
• Most standard library data objects in Swift, like String, Array, Dictionary, Int, Float, Boolean, are all structs, therefore value objects.

Repository

GitHub - paigeshin/ios_ultimate_interview_questions