In Objective-C, what is the equivalent of Java's "instanceof" keyword?

objective-c types casting equality downcast
Dimitris picture Dimitris · Feb 11, 2009 · Viewed 82.9k times · Source

I would like to check whether an object (e.g. someObject) is assignable (cast-able) to a variable of another type (e.g. SpecifiedType). In Java, I can write:

someObject instanceof SpecifiedType

A related question is finding whether the runtime type of an object is equal to a another type. In Java, I can write:

someObject.getClass().equals(SpecifiedType.class)

How can this be done in Objective-C?

Answer

mouviciel picture mouviciel · Feb 11, 2009

Try [myObject class] for returning the class of an object.

You can make exact comparisons with:

if ([myObject class] == [MyClass class])

but not by using directly MyClass identifier.

Similarily, you can find if the object is of a subclass of your class with: 

if ([myObject isKindOfClass:[AnObject class]])

as suggested by Jon Skeet and zoul.

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