note 100314 added to language.oop5.basic

What is the difference between $this and self ? Inside a class definition, $this refers to the current object, while self refers to the current class. It is necessary to refer to a class element using self , and refer to an object element using $this . Note also how an object variable must be preceded by a keyword in its definition. The following example illustrates a few cases: <?php class Classy { const STAT = 'S' ; // no dollar sign for constants (they are always static) static $stat = 'Static' ; public $publ = 'Public' ; private $priv = 'Private' ; protected $prot = 'Protected' ; function __construct( ){ } public function showMe( ){ print '<br> self::STAT: ' . self::STAT ; // refer to a (static) constant like this print '<br> self::$stat: ' . self::$stat ; // static variable print '<br>$this->stat: ' . $this->stat ; // legal, but not what you might think: empty result print '<br>$this->publ: ' . $this->publ ; // refer to an object variable like this print '<br>' ; } } $me = new Classy( ) ; $me->showMe( ) ; /* Produces this output: self::STAT: S self::$stat: Static $this->stat: $this->publ: Public */ ?> ---- Server IP: 69.147.83.197 Probable Submitter: 74.94.131.53 ---- Manual Page -- http://www.php.net/manual/en/language.oop5.basic.php Edit -- https://master.php.net/note/edit/100314 Del: integrated -- https://master.php.net/note/delete/100314/integrated Del: useless -- https://master.php.net/note/delete/100314/useless Del: bad code -- https://master.php.net/note/delete/100314/bad+code Del: spam -- https://master.php.net/note/delete/100314/spam Del: non-english -- https://master.php.net/note/delete/100314/non-english Del: in docs -- https://master.php.net/note/delete/100314/in+docs Del: other reasons-- https://master.php.net/note/delete/100314 Reject -- https://master.php.net/note/reject/100314 Search -- https://master.php.net/manage/user-notes.php