class_exists Checks if the class has been defined &reftitle.description; boolclass_exists stringclass boolautoload&true; This function checks whether or not the given class has been defined. &reftitle.parameters; class The class name. The name is matched in a case-insensitive manner. autoload Whether to autoload if not already loaded. &reftitle.returnvalues; Returns &true; if class is a defined class, &false; otherwise. &reftitle.examples; ]]> ]]> &reftitle.seealso; function_exists enum_exists interface_exists get_declared_classes