PHP - Determining an Object's Class
Introduction
To explicitly check the class of a particular object that you're working with.
To find out the class of an object, you can use PHP's built-in get_class() function, as follows:
Demo
<?php
class MyClass {
}/*from w w w . j a v a 2s . com*/
$obj = new MyClass();
echo get_class($obj); // Displays"MyClass"
?>
Result
get_class() can find out exactly which class an object belongs to.
It's more useful to know if an object is descended from a given class.
Demo
<?php
class Fruit {
}/* ww w .j a v a 2 s .co m*/
class SoftFruit extends Fruit {
}
class HardFruit extends Fruit {
}
function eatSomeFruit(array $fruitToEat) {
foreach($fruitToEat as $itemOfFruit) {
if (get_class($itemOfFruit) =="SoftFruit"|| get_class($itemOfFruit) =="HardFruit") {
echo "Eating the fruit-yummy! \n";
}
}
}
$banana = new SoftFruit();
$apple = new HardFruit();
eatSomeFruit(array($banana, $apple));
?>
Result
PHP provides a useful instanceof operator, which you can use as follows:
if($object instanceof ClassName) {...
If $object 's class is ClassName, or if $object 's class is descended from ClassName, then instanceof returns true.
Otherwise, it returns false.
So you can now rewrite the preceding eatSomeFruit() function in a more elegant fashion:
<?php
function eatSomeFruit(array $fruitToEat) {
foreach($fruitToEat as $itemOfFruit) {
if ($itemOfFruit instanceof Fruit) {
echo "Eating the fruit-yummy! \n";
}
}
}
?>