How to call a function in parent class PHP?

Question

I have two PHP classes. The first one is like :

<?php 
     $myclass = new MainClass;

     class MainClass{
              public $login;

              public function __construct(){
                  require_once('login.class.php');
                  $this->login = new login;
              }

              public function mysql(){
                  mysql_connect("localhost","root","");
              }   


     }
?>

And my Login class is :

<?php

   class Login{

           public function checkDB(){
               //**** how do I call mysql on MainClass here ?*****
          }
    }
?>

I need to mention that Login is Not child class of Main Class. So I'm wondering how to call mysql function on MainClass from Login Class ?

Answer 1

Method1: : Derived class,

<?php
require_once('MainClass.php'); // MainClass store as a php file
   class Login extends MainClass{

           public function checkDB(){
               $this->mysql(); //**** call mysql from MainClass here
          }
    }
?>

Method2: : Object instance,

<?php
require_once('MainClass.php'); // MainClass store as a php file
$check_mysql = new MainClass();

   class Login extends MainClass{

           public function checkDB(){
               $check_mysql->mysql(); //**** call mysql from MainClass here
          }
    }
?>

Note: Don't use MySQL functions because they are deprecated, so use mysqli or PDO for connecting DB.

Answer 2

use this code, you just have to create object of MainClass and call the mainClass function.

<?php

class Login{

       public function checkDB(){
           $main = new MainClass();
           $main->mysql();
      }
}
?>

Answer 3

If you want to use an object-oriented handler for this, instead of reinventing the wheel, use the mysqli class. Documentation here , code example below:

class Login extends mysqli {
  public function __construct($loginid) {
    $this->id = $loginid; // example of wrapping
    parent::__construct( /* login constants go here */ );
  }
  . . .
  // other functions that can have direct access to the mysqli:: class
}

Answer 4

As shapeshifter said in the comments, you want a class that you can reference from other classes. Instead, I would probably do something like this:

<?php
$database = new MainClass();
class Login
{
   public function checkDB($database)
   {
       $database->mysql();
   }
}
?>