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Question 1

What is OOP?

Answer 1

Object-Oriented Programming (OOP) is a programming model based on the concept of classes and objects.

Question 2

What are the advantages of OOP?

Answer 2

• Clear modular structure for programs
• Adheres to the DRY principle
• Easier to maintain, modify, and debug
• Allows for less code and shorter development time with high reusability

Question 3

Why implement OOP?

Answer 3

• Good structure of the program
• Code reusability
• Faster development
• Easier to maintain

Question 4

What are the two main aspects of OOP?

Answer 4

Classes and objects.

Question 5

Define a class in OOP.

Answer 5

A class is a self-contained, independent collection of variables and functions that work together to perform specific tasks.

Question 6

What is an object in OOP?

Answer 6

An object is an individual instance of a class.

Question 7

How does a class act in OOP?

Answer 7

A class acts as a template or blueprint from which individual objects can be created.

Question 8

What is the relationship between classes and objects?

Answer 8

Objects inherit the same generic properties and behaviors from their classes but may have different values for certain properties.

Question 9

True or False: A class can be declared using the class keyword followed by the class name and curly braces.

Answer 9

True.

Question 10

What are variables within a class called?

Answer 10

Properties.

Question 11

What are functions within a class called?

Answer 11

Methods.

Question 12

How are class names conventionally written?

Answer 12

In PascalCase, where each concatenated word starts with an uppercase letter.

Question 13

What does the arrow symbol (->) do in OOP?

Answer 13

It is used to access contained properties and methods of a given object.

Question 14

What is the purpose of the $this pseudo-variable?

Answer 14

It provides a reference to the calling object.

Question 15

What is a constructor in OOP?

Answer 15

A constructor allows initializing the object’s properties upon creation.

Question 16

How is a constructor declared in a class?

Answer 16

Using the construct() function with double underscores before ‘construct’.

Question 17

What is a destructor in OOP?

Answer 17

A destructor is called when the object is destructed or when the script is stopped or exited.

Question 18

How is a destructor declared in a class?

Answer 18

Using the destruct() function with double underscores before ‘destruct’.

Question 19

What are access modifiers?

Answer 19

Keywords that restrict access to properties and methods for greater control.

Question 20

List the three visibility keywords in OOP.

Answer 20

• public
• protected
• private

Question 21

What does the public access modifier do?

Answer 21

Allows properties or methods to be accessed anywhere within or outside of the class.

Question 22

What does the protected access modifier do?

Answer 22

Allows access only within the class itself or in inherited classes.

Question 23

What does the private access modifier do?

Answer 23

Allows access only within the class that defines it.

Question 24

What is inheritance in OOP?

Answer 24

Classes can inherit properties and methods from another class using the extends keyword.

Question 25

What distinguishes static variables from constants in OOP?

Answer 25

Static variables can change during runtime, while constants have fixed values known at compile time.

Question 26

How are static variables accessed in OOP?

Answer 26

Using the class name or the self keyword followed by the scope resolution operator :: and the static variable name.

Question 27

What is the relationship between static variables and class instances?

Answer 27

Static variables belong to the class rather than to instances of the class.

Question 28

What is a static method in OOP?

Answer 28

A method that has the same concept as static variables but in a function context.

Question 29

What keyword can be used to access static variables/methods inside a child class?

Answer 29

The parent keyword.