interface_exists Checks if the interface has been defined &reftitle.description; boolinterface_exists stringinterface boolautoload&true; Checks if the given interface has been defined. &reftitle.parameters; interface The interface name autoload Whether to autoload if not already loaded. &reftitle.returnvalues; Returns &true; if the interface given by interface has been defined, &false; otherwise. &reftitle.examples; ]]> &reftitle.seealso; get_declared_interfaces class_implements class_exists enum_exists