PHP construct and destruct

__construct() and __destruct() are the special functions of a class. PHP will automatically call construct function when object is created for a class and automatically call destruct function at the end of the script when objects are destroyed.
Both construct and destruct functions starts with two underscores (__).
__construct() function can be used to initialize the object properties, while __destruct() function can be used to release the object level resources before destruction of object before script execution completion.
__construct() function can specify parameters, When parameters specified then while creating object using new keyword arguments should be passed.
__destruct() function does not allow parameters.
When no __construct and __destruct() functions added, PHP will create default functions without parameters.
__construct() and __destruct() functions will not allow access specifiers.

function __construct() {

}

Syntax to create objects having __construct() function without parameters

$object_reference_variable = new ClassName();

function __construct($pmtr1, $pmtr2, $pmtr3 ...) {

}

Syntax to create objects having __construct() function with parameters

$object_reference_variable = new ClassName(value1, value2, value3);

PHP construct and destruct example

<?php

class Box {

public $width;

public $height;

public $depth;

function __construct($width, $height, $depth) {

echo "construct called </br>";

$this->width = $width;

$this->height = $height;

$this->depth = $depth;

}

public function volume () {

return $this->width * $this->height * $this->depth;

}

function __destruct () {

echo "destruct called";

}

$box = new Box(10, 20, 30);

echo "Volume of Box: ". $box->volume() . "</br>";

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