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<?php
class MyClass {}
class AnotherClass extends MyClass{}
$obj = new AnotherClass();
if($obj instanceof AnotherClass) {
echo "The object is AnotherClass";
}
// The object is also an instance of the class it is derived from
if($obj instanceof MyClass) {
echo "The object is MyClass<br>";
}
?>
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<?php
/*
*
* opcode number: 138
*/
$obj = new A();
if ($obj instanceof A) {
echo 'A';
}
?>
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class MyClass {
}
$o1 = new MyClass();
$o2 = new MyClass();
$name = 'MyClass';
// in the cases below, $a gets boolean value true
$a = $o1 instanceof MyClass;
$a = $o1 instanceof $name;
$a = $o1 instanceof $o2;
// counter examples:
$b = 'b';
$a = $o1 instanceof 'MyClass'; // parse error: constant not allowed
$a = false instanceof MyClass; // fatal error: constant not allowed
$a = $b instanceof MyClass; // false ($b is not an object)
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$myObject instanceof MyClass
//usualy in if()
if($myObject instanceof MyClass)
{
//Do it
}
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The instanceof keyword is used to check if an object belongs to a class. The comparison returns true if the object is an instance of the class, it returns false if it is not.