Object in PHP

An Object is an individual instance of the data structure defined by a class. We define a class once and then make many objects that belong to it. Objects are also known as instances.

Creating an Object:
Following is an example of how to create object using new operator.

class Book {
   // Members of class Book
}

// Creating three objects of book
$physics = new Books;
$maths = new Books;
$chemistry = new Books;

Member Functions:
After creating our objects, we can call member functions related to that object. A member function typically accesses members of current object only.

Example:

$physics->setTitle( \"Physics for High School\" );
$chemistry->setTitle( \"Advanced Chemistry\" );
$maths->setTitle( \"Algebra\" );

$physics->setPrice( 10 );
$chemistry->setPrice( 15 );
$maths->setPrice( 7 );

The following syntax used are for the following program elaborated in the example given below:

Example:

<?php

class Books {

/* Member variables */
var $price;
var $title;

/* Member functions */
function setPrice($par){
$this->price = $par;
}

function getPrice(){
echo $this->price.\"<br>\";
}

function setTitle($par){
$this->title = $par;
}

function getTitle(){
echo $this->title.\"<br>\" ;
}
}

/* Creating New object using \"new\" operator */
$maths = new Books;

/* Setting title and prices for the object */
$maths->setTitle( \"Algebra\" );
$maths->setPrice( 7 );

/* Calling Member Functions */
$maths->getTitle();
$maths->getPrice();
?>