如何知道方法有多少参数？

Question

Using, probably, the ReflectionClass, how could I know how many parameters is a method expecting?

class Test {
    public function mymethod($one, $two, $three = '') {}
    public function anothermethod($four) {}
}

$test = new Test();
$i = function_im_looking_for(array($test, 'mymethod'));
$i2 = function_im_looking_for(array($test, 'anothermethod'));
echo $i .' - '. $i2;

The above code should output : 3 - 1;

Answer 1

function function_im_looking_for($callable) {
    list($class, $method) = $callable;
    $reflector = new ReflectionMethod($class, $method);
    return $reflector->getNumberOfParameters();
}

It's all just about finding ReflectionMethod.