# initWithTarget:selector:object: Returns an `NSInvocationOperation` object initialized with the specified target and selector. ``` - (instancetype) initWithTarget:(id) target selector:(SEL) sel object:(id) arg; ``` ## Parameters `target` The object defining the specified selector. `sel` The selector to invoke when running the operation. The selector may take 0 or 1 parameters; if it accepts a parameter, the type of that parameter must be `id`. The return type of the method may be `void`, a scalar value, or an object that can be returned as an `id` type. `arg` The parameter object to pass to the selector. If the selector does not take an argument, specify `nil`. ## Return Value An initialized `NSInvocationOperation` object or `nil` if the target object does not implement the specified selector. ## Discussion If you specify a selector with a non-void return type, you can get the return value by calling the [`result`](/documentation/Foundation/NSInvocationOperation/result) method after the operation finishes executing. The receiver tells the invocation object to retain its arguments. ## See Also [Threading Programming Guide](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Multithreading/Introduction/Introduction.html#//apple_ref/doc/uid/10000057i) --- 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)