is_a

(PHP 4 >= 4.2.0, PHP 5, PHP 7)

is_aChecks if the object is of this class or has this class as one of its parents

Description

is_a ( mixed $object , string $class_name [, bool $allow_string = false ] ) : bool

Checks if the given object is of this class or has this class as one of its parents.

Parameters

object

A class name or an object instance.

class_name

The class name

allow_string

If this parameter set to false, string class name as object is not allowed. This also prevents from calling autoloader if the class doesn't exist.

Return Values

Returns true if the object is of this class or has this class as one of its parents, false otherwise.

Examples

Example #1 is_a() example

<?php
// define a class
class WidgetFactory
{
  var $oink = 'moo';
}

// create a new object
$WF = new WidgetFactory();

if (is_a($WF, 'WidgetFactory')) {
  echo "yes, \$WF is still a WidgetFactory\n";
}
?>

Example #2 Using the instanceof operator in PHP 5

<?php
if ($WF instanceof WidgetFactory) {
    echo 'Yes, $WF is a WidgetFactory';
}
?>

See Also

  • get_class() - Returns the name of the class of an object
  • get_parent_class() - Retrieves the parent class name for object or class
  • is_subclass_of() - Checks if the object has this class as one of its parents or implements it

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.is-a.php