Allow Dynamic Properties

This is a native PHP attribute, which tells the engine that a class can dynamically create properties without declaring them.

This attribute may be added to any class. It is not necessary with stdClass.

The attributes allow any dynamic property: there is no way to restrict this to a set of names or a number without other means.

<?php

class MyClass {
     function foo() {
             // creation of a property, without prior definition
             // This yields an error
             $this->p  = 1;
     }
}

#[AllowDynamicProperty]
class MyOtherClass {
     function foo() {
             // creation of a property, without prior definition
             // This doesn't yields an error
             $this->p  = 1;
     }
}

class MyThirdClass extends Stdclass {
     function foo() {
             // creation of a property, without prior definition
             // This doesn't yields an error, yet no attribute
             $this->p  = 1;
     }
}

?>

Documentation

See also No More Dynamic Properties in PHP 9., I hate the deprecation of dynamic properties.

Related : PHP Native Attribute

Added in PHP 8.2+