How to use a constructor in PHP with example 2021

How to use a constructor in PHP with example

PHP Contractor: PHP is a server-side web programming language that is often used as a replacement for ASP, JSP, and ASP.NET.

It allows you to create dynamic web pages by executing code on the server-side. In this article, we will show you how to use a PHP constructor to generate your HTML pages dynamically using the server-side scripting language.

The steps are as follows:

1. Create an HTML file with the following content:

2. Insert PHP tags around variables and values which you want to dynamically change:

3. Include a PHP script at the top of your file:

4. This is my dynamically generated page!";?

Constructor: It is a special member function of a class that executes when we create the instance(object) of that class. in other words, we can say that there is no need to call a constructor. PHP provides a special function called __construct() to define a constructor. construct() function start with two underscore. It may be parameterized or non-parameterized.

How to use Constructor without parameters in PHP?

<?PHP

class Rectangle

{

public $h;

public $w;

public $area;

function __construct()

{

$this->h = 20;

$this->w = 20;

$this->area = $this->h*$this->w;

echo "Area of Rectangle:".$this->area;

}

$r=new Rectangle();

*****OUTPUT*****

Area of Rectangle:400

How to use Constructor with parameter in PHP?

<?php

class Rectangle

{

public $height;

public $width;

public $area;

function __construct($h,$w)

{

$this->height = $h;

$this->width = $w;

$this->area = $this->height*$this->width;

echo "Area of Rectangle:".$this->area;

}

$r=new Rectangle(20,20);

*****OUTPUT*****

Area of Rectangle:400

Destructor: It is also a special member function of a class that executes when the work of an object goes out of scope. PHP provides a special function called __destruct() to define a destructor. destruct() function starts with two underscores. Destructor is called at the end of the script.

How to use Constructor with parameters in PHP?

<?PHP

class Intro

{

public $name;

public $marks;

function __construct($n,$m)

{

$this->name = $n;

$this->marks = $m;

}

function __destruct()

{

echo "Student Name:".$this->name."<br>";

echo "Student Marks:".$this->marks;

}

$student = new Intro("Icoderweb",2022);

*****OUTPUT*****

Student Name:Icoderweb

Student Marks:2022

How to use constructor in php with example 2022