Question

Is there anyway to see if an object specifically implements ->__toString? This doesn’t seem to work:

method_exists($object, '__toString');

Answer 1

There are two way to check it.

Lets assume you have classes:

class Foo
{
    public function __toString()
    {
        return 'foobar';
    }
}

class Bar
{
}

Then you can do either:

$rc = new ReflectionClass('Foo');       
var_dump($rc->hasMethod('__toString'));

$rc = new ReflectionClass('Bar');       
var_dump($rc->hasMethod('__toString'));

or use:

$fo = new Foo;
var_dump( method_exists($fo , '__toString'));
$ba = new Bar;
var_dump( method_exists($ba , '__toString'));

Difference is that in first case the class is not actually instantiated.
You can look at demo here : http://codepad.viper-7.com/B0EjOK