PHP/Language Basics/instanceof

Difference between instanceof and is_subclass_of( )

   <source lang="html4strict">

<?

   class Dog { }
   class Poodle extends Dog { }
   $poppy = new Poodle( );
   print (int)($poppy instanceof Poodle);
   print "\n";
   print (int)is_subclass_of($poppy, "Poodle");

?>

 </source>
   
  

Using the instanceof Operator

   <source lang="html4strict">

<?php

    class Math {
         public function add($op1, $op2) {
              if(($op1 instanceof Float) && ($op2 instanceof Float)) {
                   return $op1->getFloat() + $op2->getFloat();
              } else {
                   echo "Must pass two Floats!\n";
              }
         }
    }

?>

 </source>