php - instanceof equivalent for a string-represented classname

Question

I'm looking for a functionality, in the example below called "theFunctionILookFor", that will make the code work.

$myClassName = "someName";
$parentOrInterfaceName = "someParent";
if (theFunctionILookFor($myClassName)) {
    echo "is parent";
}

Edit: I try to avoid instantiating the class just to perform this check. I would like to be able to pass 2 string parameters to the checking function

question from:https://stackoverflow.com/questions/4618550/instanceof-equivalent-for-a-string-represented-classname

Answer 1

Looks like this is my answer: is_subclass_of

It can accept both parameters as strings

http://php.net/manual/en/function.is-subclass-of.php