PHP Classes and Objects

Here you will learn about classes and objects in PHP with examples.

Classes and objects becomes useful in PHP when writing long and repetitive code, as using classes and objects, you can make your code more efficient and less repetitive just by grouping all similar tasks avaialable in your PHP code/program.

PHP Class

PHP class is a programmer-defined datatype, which includes the local functions as well as the local data.

You can say that, class contains methods and properties.

You can define some particular action using class just to build objects.

PHP Object

In PHP, after creating and defining class, objects are then built using the predefined structure.

PHP object is an individual instance of the data structure defined by a class.

You define a class once and then can make many objects that belongs to it.

You can also called objects as instance.

PHP Classes and Objects Example

Here is an example demonstrating classes and objects in PHP.

<!DOCTYPE html>
<html>
<head>
   <title>Classes and Objects Example in PHP</title>
</head>
<body>
<?php
   class Like
   {
      public static function whatILike()
      {
         echo "I just love to read everything on CodesCracker";
      }
   }
   Like::whatILike();
?>
</body>
</html>

Below is the sample output of the above classes and objects example code.

Let's expand the above class and object example code in PHP.

<!DOCTYPE html>
<html>
<head>
   <title>Classes and Objects Example in PHP</title>
</head>
<body>
<?php
   class Like
   {
      public static function whatILike()
      {
         echo "I just love to read everything on CodesCracker";
      }
      public static function say()
      {
         self::whatILike();
      }
   }
   class LikeAnother extends Like 
   {
      public static function whatILike()
      {
         echo "I just love to read PHP on CodesCracker";
      }
   }
   Like::say();
   echo "<br/>";
   LikeAnother::say();
   echo "<br/>";
   LikeAnother::whatILike();
?>
</body>
</html>

Here is the sample output produced by the above classes and objects example code in PHP.

Let's take one more example that illustrates about class and object in PHP.

<!DOCTYPE html>
<html>
<head>
   <title>Classes and Objects Example in PHP</title>
</head>
<body>
<?php
   class class_name
   {
      public function __construct(array $args_var=array())
      {
         if(!empty($args_var))
         {   
            foreach($args_var as $property_var=>$argument)
            {
               $this->{$property_var}=$argument;
            }
         }
      }
      public function __call($method, $args_var)
      {
         $args_var = array_merge(array("class_name" => $this), $args_var); 
         return call_user_func_array($this->{$method}, $args_var);
      }
   }
   $class_name_Object = new class_name();
   $class_name_Object->name = "Codes";
   $class_name_Object->surname = "Cracker";
   $class_name_Object->what = "everything";
   $class_name_Object->getInfo = function($class_name)
   {
      echo "I just love to read ".$class_name->what." on ".$class_name->name.$class_name->surname;
   };
   $class_name_Object->getInfo();
?>
</body>
</html>

Below is the sample output produced by the above class and object example program.

Here is another example on class and object in PHP.

<!DOCTYPE html>
<html>
<head>
   <title>Classes and Objects Example in PHP</title>
</head>
<body>
<?php
   class EnumClass
   {
      protected $self_var = array();
      public function __construct()
      {
         $arguments_var = func_get_args();
         for($i=0,$n=count($arguments_var); $i<$n; $i++)
         {
            $this->adding_fun($arguments_var[$i]);
         }
      }
      public function __get($name=null)
      {
         return $this->self_var[$name];
      }
      public function adding_fun($name=null, $enumVar=null)
      {
         if(isset($enumVar))
         {
            $this->self_var[$name]=$enumVar;
         }
         else
         {
            $this->self_var[$name]=end($this->self_var)+1;
         }
      }
   }
   class FlagsEnumClass extends EnumClass
   {
      public function __construct()
      {
         $arguments_var=func_get_args();
         for($i=0,$n=count($arguments_var),$f=0x1; $i<$n; $i++,$f*=0x2)
         {
            $this->adding_fun($arguments_var[$i], $f);
         }
      }
   }
   // this will print 1, 2, 3
   $tutorials = new EnumClass("PHP", "HTML", "CSS");
   echo $tutorials->PHP . ", ";
   echo $tutorials->HTML . ", ";
   echo $tutorials->CSS;
   
   echo "<hr/>";
   
   // this will print 1, 2, 4, 8
   $thisTutorialTopic = new FlagsEnumClass("PHP", "Classes", "Objects", "Examples");
   echo $thisTutorialTopic->PHP . ", ";
   echo $thisTutorialTopic->Classes . ", ";
   echo $thisTutorialTopic->Objects . ", ";
   echo $thisTutorialTopic->Examples;
?>
</body>
</html>

The above example code on classes and objects in PHP will produce the output given below: