# responds(to:) Returns a Boolean value that indicates whether the receiver implements or inherits a method that can respond to a specified message. ``` func responds(to aSelector: Selector!) -> Bool ``` ## Parameters `aSelector` A selector that identifies a message. ## Return Value [`YES`](/documentation/ObjectiveC/YES) if the receiver implements or inherits a method that can respond to `aSelector`, otherwise [`NO`](/documentation/ObjectiveC/NO). ## Discussion The application is responsible for determining whether a [`NO`](/documentation/ObjectiveC/NO) response should be considered an error. You cannot test whether an object inherits a method from its superclass by sending [`responds(to:)`](/documentation/ObjectiveC/NSObjectProtocol/responds(to:)) to the object using the `super` keyword. This method will still be testing the object as a whole, not just the superclass’s implementation. Therefore, sending [`responds(to:)`](/documentation/ObjectiveC/NSObjectProtocol/responds(to:)) to `super` is equivalent to sending it to `self`. Instead, you must invoke the `NSObject` class method [`instancesRespond(to:)`](/documentation/ObjectiveC/NSObject-swift.class/instancesRespond(to:)) directly on the object’s superclass, as illustrated in the following code fragment. ```objc if( [MySuperclass instancesRespondToSelector:@selector(aMethod)] ) { // invoke the inherited method [super aMethod]; } ``` You cannot simply use `[[self superclass] instancesRespondToSelector:@selector(aMethod)]` since this may cause the method to fail if it is invoked by a subclass. Note that if the receiver is able to forward `aSelector` messages to another object, it will be able to respond to the message, albeit indirectly, even though this method returns [`NO`](/documentation/ObjectiveC/NO). ## See Also [`instancesRespond(to:)`](/documentation/ObjectiveC/NSObject-swift.class/instancesRespond(to:)) Returns a Boolean value that indicates whether instances of the receiver are capable of responding to a given selector. [`forwardInvocation:`](/documentation/ObjectiveC/NSObject-swift.class/forwardInvocation:) Overridden by subclasses to forward messages to other objects. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)