What is the difference between constructor and destructor in php

The difference between constructors and destructors in php is: 1. The constructor can receive parameters and can be assigned to object properties when creating an object. The destructor cannot take parameters; 2. The constructor is called when creating an object. Function, the destructor is automatically called when the object is destroyed.

Difference analysis:

Constructor

Classes with a constructor will first call this method each time an object is created.

void __construct ([ mixed $args [, $... ]] )

• The constructor can receive parameters and can be assigned to object properties when creating the object

• The constructor can call class methods or other functions

• The constructor can call the constructor of other classes

Example

<?php
class BaseClass {
   function __construct() {
       print "In BaseClass constructor\n";
   }
}

class SubClass extends BaseClass {
   function __construct() {
       parent::__construct();
       print "In SubClass constructor\n";
   }
}

$obj = new BaseClass();
$obj = new SubClass();
?>

Destructor

void __destruct ( void )

• The destructor is in When the object is destroyed, it is called automatically and cannot be called explicitly.

• The destructor cannot take parameters

Example:

<?php
class MyDestructableClass {
   function __construct() {
       print "In constructor\n";
       $this->name = "MyDestructableClass";
   }

   function __destruct() {
       print "Destroying " . $this->name . "\n";
   }
}

$obj = new MyDestructableClass();
?>

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