PHP | ReflectionClass isInstance() Function Last Updated : 12 Jul, 2025 Comments Improve Suggest changes Like Article Like Report The ReflectionClass::isInstance() function is an inbuilt function in PHP which is used to check whether the specified object is an instance of the class or not. Syntax: bool ReflectionClass::isInstance( object $object ) Parameters: This function accepts a single parameter object which is being searched in the instance of the class. Return Value: This function returns true for the success or false on failure. Below programs illustrate the ReflectionClass::isInstance() function in PHP: Program 1: php <?php // Declaring a user-defined class class GFG { } // Initialising the instance $Instance = new GFG(); // Using ReflectionClass over the // instance GFG $obj = new ReflectionClass('GFG'); // Calling isInstance() function $A = $obj->isInstance($Instance); // Getting the value true or false var_dump($A); ?> Output: bool(true) Program 2: php <?php // Declaring a user-defined class class GFG { } // Using ReflectionClass over the // instance GFG $obj = new ReflectionClass('GFG'); // Calling isInstance() function $A = $obj->isInstance($obj); // Getting the value true or false var_dump($A); ?> Output: bool(false) Reference: https://www.php.net/manual/en/reflectionclass.isinstance.php Comment More info K Kanchan_Ray Follow Improve Article Tags : Web Technologies PHP PHP-function PHP- ReflectionClass PHP- Reflection +1 More Explore PHP Tutorial 8 min read BasicsPHP Syntax 4 min read PHP Variables 5 min read PHP | Functions 8 min read PHP Loops 4 min read ArrayPHP Arrays 5 min read PHP Associative Arrays 4 min read Multidimensional arrays in PHP 5 min read Sorting Arrays in PHP 4 min read OOPs & InterfacesPHP Classes 2 min read PHP | Constructors and Destructors 5 min read PHP Access Modifiers 4 min read Multiple Inheritance in PHP 4 min read MySQL DatabasePHP | MySQL Database Introduction 4 min read PHP Database connection 2 min read PHP | MySQL ( Creating Database ) 3 min read PHP | MySQL ( Creating Table ) 3 min read PHP AdvancePHP Superglobals 6 min read PHP | Regular Expressions 12 min read PHP Form Handling 4 min read PHP File Handling 4 min read PHP | Uploading File 3 min read PHP Cookies 9 min read PHP | Sessions 7 min read Like