OOP

Question 1

A programming model that is based on the concept of classes and objects.

Answer 1

Object-Oriented Programming (OOP)

Question 2

T or F

OOP has no advantages over conventional or procedural style of programming.

Answer 2

F

OOP has several advantages over conventional or procedural style of programming.

Question 3

Advantages of OOP?

Answer 3

• It provides a clear modular structure for the programs.
• It helps you adhere to the “don’t repeat yourself (DRY) principle, thus make your code much easier to maintain, modify and debug.
• It makes it possible to create methods with less code and shorter development time with high degree of reusability.

Question 4

Why implement OOP?

Answer 4

1. Good structure of the program
2. Code reusability
3. Faster development
4. Easier to maintain
5. Laravel implements OOP concepts

Question 5

The two main aspects of OOP are:

Answer 5

Classes and Objects

Question 6

A self-contained, independent collection of variables and functions which work together to perform one or more specific tasks.

Answer 6

Class

Question 7

Individual instances of a class

Answer 7

Object

Question 8

A class acts as _____ or _____from which individual objects can be created.

Answer 8

template / blueprint

Question 9

T or F

When individual objects are created, they inherit the same generic properties and behaviors.

Answer 9

T

Question 10

T or F

Each object cannot have different values for certain properties.

Answer 10

F

Each object may have different values for certain properties.

Question 11

How do you declare a class?

Answer 11

1. the class keyword
2. the name of the class
3. a pair of curly braces {}

Question 12

Variables within a class are called ____, while functions are called ____.

Answer 12

properties, methods

Question 13

Class names are also conventionally written in ____ i.e. each concatenated word starts with an uppercase letter (e.g. MyClass).

Answer 13

PascalCase

Question 14

An OOP construct that is used to access contained properties and methods of a given object.

Answer 14

arrow symbol (->)

Question 15

The pseudo-variable ____ provides a reference to the calling object.

Answer 15

$this

Question 16

Allows to initialize the object’s properties upon creation of the object.

Answer 16

Constructor

Question 17

We use _____ function to declare constructor inside the class.

Answer 17

__construct()

Question 18

T or F

Constructor and destructor functions uses two underscores in declaration

Answer 18

T

Question 19

Called when the object is destructed or the script is stopped or exited.

Answer 19

Destructor

Question 20

T or F

__destruct function will be called at the beginning of the script.

Answer 20

F

__destruct function will be called at the end of the script.

Question 21

T or F

Constructor is invoked automatically every time you create an object.

Answer 21

T

Question 22

T or F

Destructor is invoked automatically every time you create a __destruct() function.

Answer 22

T

Question 23

When working with classes, you can even restrict access to its properties and methods using the _________ for greater control.

Answer 23

visibility keywords (access modifiers)

Question 24

A method can be accessed anywhere within or outside of class. Default in PHP

Answer 24

public

Question 25

A method that can only be accesses within the class itself or in inherited classes.

Answer 25

protected

Question 26

A method is accessible only within the class that defines it.

Answer 26

private

Question 27

Classes can inherit the properties and methods of another class using the ___keyword.

Answer 27

extends

Question 28

It is probably the most powerful reason behind using the object-oriented programming model.

Answer 28

Inheritance

Question 29

These variables are different but their values are known and fixed in compile time.

Answer 29

Constant and Static variables

Question 30

T or F Unlike static, constant variable values can be changed during runtime

Answer 30

F Unlike constant, static variable values can be changed during runtime.

Question 31

T or F If a static variable is used inside a class it belongs to the instance of the class rather than the class.

Answer 31

F If a static variable is used inside a class it belongs to the class rather than the instance of the class.

Question 32

To access static variable (outside or inside the class), you need to use the ____ or ____. Followed by the _____ and the _______, starting with $.

Answer 32

1. class name or the self keyword (if inside the class) 2. scope resolution operator :: 3. name of the static variable

Question 33

____ methods have the same concept of Static variables but in a function way.

Answer 33

Static

Question 34

We can use the ______ keyword when accessing static variables/methods inside a child class.

Answer 34

parent