Componere\Abstract\Definition::addTrait

(Componere 2 >= 2.1.0)

Componere\Abstract\Definition::addTrait — Add Trait

说明

public Componere\Abstract\Definition::addTrait ( string $trait ) : Definition

Shall use the given trait for the current definition

参数

trait: The case insensitive name of a trait

返回值

The current Definition

Exceptions

Warning

Shall throw RuntimeException if Definition was registered

User Contributed Notes

ASchmidt at Anamera dot net 23-Mar-2018 12:22


Adding a trait is an efficient way to extend a "final" class, overriding methods and adding new ones, without having to individually add each method as a closure. It also results in more readable code.



<?php

declare(strict_types=1);



/*

 *  Final class would normally prevent extending.

 */

final class ParentC

{

    public $parentvar;

    public $secondvar;

    

    function __construct() { echo( "\r\n<br/>".$this->parentvar = 'set by '.get_class().'->parentconstruct' ); }

    function parentf() { echo( "\r\n<br/>".get_class().'->parentf >> '.$this->parentvar ); }

}



/*

 *  Extended class members.

 */

trait ChildC /* extends ParentC */

{

    function __construct() {

        // Call parent constructor.

        parent::__construct();

        // Access an inherited property set by parent constructor.

        echo( "\r\n<br/>".get_class().'->overridden_constructor >> '.$this->parentvar );

    }

    

    function parentf() {

        // Call overridden parent method.

        parent::parentf();

        // Access an inherited property set by constructor.

        echo( "\r\n<br/>".get_class().'->overridden_parentf >> '.$this->parentvar );

    }

    

    function dynamicf( $parm = null ) {

        // Populate a parent class property.

        $this->secondvar = empty( $parm ) ? 'set by '.get_class().'->dynamicf' : $parm;

        // Access an inherited property set by parent constructor.

        echo( "\r\n<br/>".get_class().'->dynamicf >> '.$this->parentvar );

    }

}



/*

 *  Register the dynamic child class "ChildC", which is

 *  derived by extending "ParentC" with members supplied as "ChildC" trait.

 */

$definition = new \Componere\Definition( 'ChildC', ParentC::class );

$definition->addTrait( 'ChildC' );

$definition ->register();



/*

 *  Instantiate the dynamic child class,

 *  and access its own and inherited members.

 */

$dyno = new ChildC;

$dyno->parentf();

$dyno->dynamicf( 'myvalue ');



// Our object is also recognized as instance of parent!

var_dump( $dyno instanceof ChildC, $dyno instanceof ParentC, is_a( $dyno, 'ParentC') );

var_dump( $dyno );

?>



will output:



set by ParentC->parentconstruct 

ChildC->overridden_constructor >> set by ParentC->parentconstruct 

ParentC->parentf >> set by ParentC->parentconstruct 

ChildC->overridden_parentf >> set by ParentC->parentconstruct 

ChildC->dynamicf >> set by ParentC->parentconstruct



boolean true

boolean true

boolean true



object(ChildC)[2]

  public 'parentvar' => string 'set by ParentC->parentconstruct' (length=31)

  public 'secondvar' => string 'myvalue ' (length=8)