PHP TUTORIALS - PHP Object Oriented

PHP Object Oriented

Defining PHP Classes:


<?php
class phpClass{
   var $var1;
   var $var2 = "constant string";
   function myfunc ($arg1, $arg2) {
      [..]
   }
   [..]
}
?>

Creating Objects in PHP


   $physics = new Books;
   $maths = new Books;
   $chemistry = new Books;

Calling Member Functions


   $physics->setTitle( "Physics for High School" );
   $chemistry->setTitle( "Advanced Chemistry" );
   $maths->setTitle( "Algebra" );

   $physics->setPrice( 10 );
   $chemistry->setPrice( 15 );
   $maths->setPrice( 7 );


   $physics->getTitle();
   $chemistry->getTitle();
   $maths->getTitle();
   $physics->getPrice();
   $chemistry->getPrice();
   $maths->getPrice();


  Physics for High School
  Advanced Chemistry
  Algebra
  10
  15
  7

Constructor Functions:


function __construct( $par1, $par2 ){
   $this->price = $par1;
   $this->title = $par2;
}


   $physics = new Books( "Physics for High School", 10 );
   $maths = new Books ( "Advanced Chemistry", 15 );
   $chemistry = new Books ("Algebra", 7 );

   /* Get those set values */
   $physics->getTitle();
   $chemistry->getTitle();
   $maths->getTitle();

   $physics->getPrice();
   $chemistry->getPrice();
   $maths->getPrice();


  Physics for High School
  Advanced Chemistry
  Algebra
  10
  15
  7

Inheritance:


  class Child extends Parent {
     <definition body>
  }


class Novel extends Books{
   var publisher;
   function setPublisher($par){
     $this->publisher = $par;
   }
   function getPublisher(){
     echo $this->publisher. "<br />";
   }
}

Function Overriding:


    function getPrice(){
       echo $this->price . "<br/>";
       return $this->price;
    }
    function getTitle(){
       echo $this->title . "<br/>";
       return $this->title;
    }

Private members:


class MyClass {
   private $car = "skoda";
   $driver = "SRK";

   function __construct($par) {
      // Statements here run every time
      // an instance of the class
      // is created.
   }
   function myPublicFunction() {
      return("I'm visible!");
   }
   private function myPrivateFunction() {
      return("I'm  not visible outside!");
   }
}

Protected members:


class MyClass {
   protected $car = "skoda";
   $driver = "SRK";

   function __construct($par) {
      // Statements here run every time
      // an instance of the class
      // is created.
   }
   function myPublicFunction() {
      return("I'm visible!");
   }
   protected function myPrivateFunction() {
      return("I'm  visible in child class!");
   }
}

Interfaces:


interface Mail {
   public function sendMail();
}


class Report implements Mail {
   // sendMail() Definition goes here
}

Constants:


class MyClass {
   const requiredMargin = 1.7;
   function __construct($incomingValue) {
      // Statements here run every time
      // an instance of the class
      // is created.
   }
}

Abstract Classes:


abstract class MyAbstractClass {
   abstract function myAbstractFunction() {
   }
}

Static Keyword:


<?php
class Foo
{
    public static $my_static = 'foo';

    public function staticValue() {
        return self::$my_static;
    }
}
print Foo::$my_static . "\n";
$foo = new Foo();
print $foo->staticValue() . "\n";

Final Keyword:


<?php
class BaseClass {
   public function test() {
       echo "BaseClass::test() called<br>";
   }
  
   final public function moreTesting() {
       echo "BaseClass::moreTesting() called<br>";
   }
}

class ChildClass extends BaseClass {
   public function moreTesting() {
       echo "ChildClass::moreTesting() called<br>";
   }
}
?>

Calling parent constructors:


class Name
{
   var $_firstName;
   var $_lastName;
   function Name($first_name, $last_name)
   {
     $this->_firstName = $first_name;
     $this->_lastName = $last_name;
   }
   function toString() {
     return($this->_lastName .", " .$this->_firstName);
   }
}
class NameSub1 extends Name
{
   var $_middleInitial;
   function NameSub1($first_name, $middle_initial, $last_name) {
       Name::Name($first_name, $last_name);
       $this->_middleInitial = $middle_initial;
   }
   function toString() {
       return(Name::toString() . " " . $this->_middleInitial);
   }
}