<?php
class Foo
{
public function bar(\DateTime $datetime)
{
}
}
class Baz extends Foo
{
}
$param = new \ReflectionParameter(['Baz', 'bar'], 0);
var_dump($param->getDeclaringClass());
The above example will output:
object(ReflectionClass)#2 (1) {
["name"]=>
string(3) "Foo"
}