CODEWITHSUNDEEP
phpinheritance
Trevor
Trevor

Reputation: 13437

PHP: How do I call all methods of the same name in a class hierarchy?

I have a class hierarchy like the following:

class Alpha {
    public function initialize() {
        $class = get_class($this);
        $family = array( $class );
        while( ($class = get_parent_class($class)) !== false ) {
            $family[] = $class;
        }
        $family = array_reverse($family);
        foreach($family as $className) {
            // call $className's start (instance) method
        }
    }

    public function start() {
        echo "calling start from Alpha\n";
    }
}

class Beta extends Alpha {
    public function start() {
        echo "calling start from Beta\n";
    }
}

class Charlie extends Beta {
    public function start() {
        echo "calling start from Charlie\n";
    }
}

$c = new Charlie();
$c->initialize();

Alpha's initialize method should call the derived class's start method as well as all of the derived class's ancestor classes' start methods all the way back to Alpha's start method. The code should produce the following output:

calling start from Alpha
calling start from Beta
calling start from Charlie

However, I can't seem to figure out how to call an instance method of a specific ancestor class specified by the $className variable.

I've used call_user_func(array($className, 'start')) but this causes the start method to be treated like a static function. Any ideas?

Upvotes: 2

Views: 200

Answers (2)

Sergey
Sergey

Reputation: 5207

In class function call like Classname::start should call Classname's function start not static call

class Alpha {

    public $myvar = 0;

    public function initialize() {

        $class = get_class($this);
        $family = array( $class );
        while( ($class = get_parent_class($class)) !== false ) {
            $family[] = $class;
            $this->myvar ++;
        }
        $family = array_reverse($family);
        foreach($family as $className) {
            // call $className's start method
            eval("{$className}::start();");
        }
    }

    public function start() {
        echo "{$this->myvar} calling start from Alpha\n";
    }
}

class Beta extends Alpha {
    public function start() {
        echo "{$this->myvar} calling start from Beta\n";
    }
}

class Charlie extends Beta {
    public function start() {
        echo "{$this->myvar} calling start from Charlie\n";
    }
}

$c = new Charlie();
$c->initialize();

Upvotes: 2

Sergey
Sergey

Reputation: 5207

class Alpha {
    public function initialize() {
        // ... call all 'start' methods in class hierarchy starting with highest level     class (Alpha's start method) and ending with lowest derived class
    }

    public function start() {
        echo "calling start from Alpha\n";
    }
}

class Beta extends Alpha {
    public function start() {
        echo "calling start from Beta\n";
        parent::start();
    }
}

class Charlie extends Beta {
    public function start() {
        echo "calling start from Charlie\n";
        parent::start();
    }

    public function initialize() {
        $this->start();
    }
}

$c = new Charlie();
$c->initialize();

Upvotes: 2

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