The instanceof keyword in JavaScript can be quite confusing when it is first encountered, as people tend to think that JavaScript is not an object-oriented programming language. What is it? What pr...

The java instanceof operator is used to test whether the object is an instance of the specified type (class or subclass or interface). The instanceof in java is also known as type comparison operator as it …

instanceof is used to check if an object is an instance of a class, an instance of a subclass, or an instance of a class that implements a particular interface. Read more from the Oracle language …

The syntax is a instanceof Bref not a instanceof Bref.class. The second argument to the instanceof operator is a class name, not an expression resolving to a class object instance.

In my particular case: callback instanceof Function or typeof callback == "function" does it even matter, what's the difference? Additional Resource: JavaScript-Garden typeof vs instanceof

Cannot perform instanceof check against type parameter E. Use instead its erasure Object since generic type information will be erased at runtime What is the better way to do it?

Nov 21, 2012 · 7 You do an instanceof check of a reference against an instance, and it checks the type of instance that particular reference is pointing to. Now since you can create a reference of an …

Otherwise, use instanceof. Note that with getClass() you will need to ensure you have a non-null reference to start with, or you'll get a NullPointerException, whereas instanceof will just return false if …

Jun 27, 2014 · One way would be to use instanceof Obj2 and instanceof Obj3. Since both objects were created with Obj1.prototype in their prototype chain, it makes sense that they identify as being an …

Is instanceof considered bad practice? If so, under what circumstances is instanceof still preferable? Asked 15 years, 9 months ago Modified 6 years, 11 months ago Viewed 50k times