Question 1

Although the destructor function is always called, a constructor function is only called when you instantiate a new class object.

Accepted Answer

The constructor function is called only when a new object of the class is created. The destructor function is called when an object is destroyed or goes out of scope.

Question 2

Methods and properties that are required for a source program to communicate with an object are referred to as a(n) ____.

Accepted Answer

The methods and properties required to communicate with an object are defined in the interface of the object, which specifies how other objects can interact with it. Therefore, the correct choice is A, interface. B, attribute, refers to the specific values stored in an object. C, function, is a specific block of code that performs a task. D, class, is a blueprint for creating objects and defining their initial properties and behavior. While all of these concepts are related to object-oriented programming, only interface specifically refers to the methods and properties required for communication with an object.

Question 3

A constructor function is a special function that is called automatically when an object from a class is instantiated.

Accepted Answer

The constructor function is a special function that is automatically called when an instance of a class is created. It is used to initialize the properties of the newly created object.

Question 4

When you serialize an object with the serialize() function, PHP looks in the object's class for a special function named __sleep() function, which you can use to perform many of same tasks as a destructor function.

Accepted Answer

When you serialize an object with the serialize() function, PHP looks in the object's class for a special function named __sleep() function, which you can use to perform many of same tasks as a destructor function.

Question 5

Objects are often called ____.

Accepted Answer

Objects are made up of components or modules, each of which has its own properties and behavior, which can be reused in other programs or combined with other components to create new software solutions.

Question 6

Access specifiers control a client's access to individual data members and member functions.

Accepted Answer

Access specifiers, such as public, private, and protected, determine the level of access a client has to the data members and member functions of a class. This is one of the key principles of encapsulation in object-oriented programming.

Question 7

Objects are organized into ____.

Accepted Answer

Objects are organized into classes. Classes define the properties, methods, and behavior of objects, and allow for the creation of multiple instances of the same class. Programs, instances, and functions are all related to objects and classes, but they do not directly organize objects.

Question 8

The principle of information hiding states that any class members that other programmers, sometimes called clients, do not need to access or know about should be hidden.

Accepted Answer

This principle encourages encapsulating the implementation details of a class and only exposing the necessary interface to the other classes or modules. This helps in achieving a better design, reduces complexity, and protects the internal state and behavior of the class from unauthorized access and modifications.

Question 9

Programming code and data that can be treated as an individual unit or component is known as a(n) ____.

Accepted Answer

An object is a self-contained unit that consists of both data (attributes) and functions (methods) that can interact with each other. Therefore, programming code and data that can be treated as an individual unit or component is known as an object. Methods are functions that belong to an object and attributes are the data stored within an object.

Question 10

Serialization refers to the process of converting an object into binary data that you can store for reuse.

Accepted Answer

Serialization refers to the process of converting an object into a format (often binary or text) that can be easily stored or transmitted and later reconstructed. It is not limited to binary data.

Question 11

Accessor functions are private member functions that a client can call to retrieve or modify the value of a data member.

Accepted Answer

Accessor functions are actually public member functions that provide access to private data members of a class. They are also called getter functions. They do not modify the value of a data member but only retrieve it. Setter functions are used to modify the value of a private data member.

Question 12

An object created from an existing class is called a(n) ___

Accepted Answer

An object created from an existing class is called an instance. This is because each object created will be an individual representation of that class, with its own set of properties and methods. The other choices (method, property, and variable) all refer to specific elements within a class, but do not encompass the entire object.

Question 13

____ are variables associated with an object.

Accepted Answer

Properties are variables associated with an object. Components refer to individual parts that make up a larger system, elements usually refer to basic building blocks or parts of a larger entity, and parameters are variables used in functions or methods to customize behavior.

Question 14

Reusable software objects that can be incorporated into multiple programs is called ____.

Accepted Answer

Reusable software objects are a fundamental concept in object-oriented programming. Option A is incorrect because object-based programming is a conception (not a standard term) that only partially implements the concepts of OOP (no inheritance, and limited polymorphism). Option C is incorrect because snippets typically refer to small pieces of code that are not necessarily reusable objects. Option D is also not a good choice because functions are usually not complete objects and don't necessarily facilitate reusable code.

Question 15

____ are functions associated with an object.

Accepted Answer

Methods are functions associated with an object. Properties are characteristics of an object, and data refers to the information stored within a program. Return functions are not a standard programming term.

Question 16

Information contained within variables is called ____.

Accepted Answer

Variables store data, therefore the information contained within a variable is referred to as data.

Question 17

There are three levels of access specifiers in PHP: public, private, and protected.

Accepted Answer

This is true, PHP has three levels of access specifiers: public, private, and protected.

Question 18

A destructor function cleans up any resources allocated to an object after the object is destroyed.

Accepted Answer

The destructor function is called automatically when the object is destroyed and is responsible for releasing any resources allocated to the object.

Question 19

The public access specifier allows anyone to call a class's member function or to modify or retrieve the value of a data member.

Accepted Answer

The public access specifier in a class allows anyone to call its member functions, and access or modify the values of its data members.

Question 20

Objects in which all code and required data are contained within the object itself are ____.

Accepted Answer

The term "encapsulation" refers to the practice of containing all code and necessary data within an object. This helps to ensure that the object is well-defined and self-contained, making it easier to use and manage within a larger program. Therefore, the best choice is D - encapsulated. A, B, and C are not correct because they do not accurately describe the concept of encapsulation.

Quiz 10: Developing Object-Oriented Php