Page 330 - Computer Software Application TP - Volume 1
P. 330
COMPUTER SOFTWARE APPLICATION - CITS
EXERCISE 60 : Perform class constants, Class inheritance,
Abstract classes and methods, Object
serialization, checking for class and
method, existence, Exceptions, Iterators
Objectives
At the end of this exercise you shall be able to
• use inheritance and abstract classes in PHP
• use object serialization in PHP
• use exceptions and lterators in PHP.
Requirements
Tools/Materials
• Computer/Laptop with latest configuration • PHP
• Operating system: windows 10 or 11 • Text editor
• Apache web server • Web browser
Procedure
TASK 1: Using class constants
1 Open the text editor
2 Write the following codes
<html >
<head>
<title> class constants </title>
</head>
<body>
<?php
class MathConstants
{
const PI = 3.14159;
const E = 2.71828;
public function printConstants()
{
echo “The value of PI is: “ . self::PI . “<br/>”;
echo “The value of E is: “ . self::E . “<br/>”;
}
}
class Circle
{
315
