Check if a class has a field by string

Question

I would Google this, but honestly I have no idea what to search for

Say I have this class

class a
{
    public $a_a, $a_b, $a_c;
}

$true = "a_a";
$false = "a_e";

How do I use the strings to prove that the class contains the field a_a, but not a_e ?

Thanks

Answer 1

With

• property_exists — Checks if the object or class has a property

In your case:

var_dump( property_exists('a', 'a_a') ); // TRUE

You could also use the Reflection API, but that's overkill for this UseCase:

$reflector = new ReflectionClass('a');
var_dump( $reflector->hasProperty('a_e') ); // FALSE

Answer 2

You could use property_exists or Reflection. But you should know that before PHP 5.3 property_exists checked the visibility of the property, too. So, if you are using PHP 5.2 and want to check the existence of a private property you must use Reflection.