What is the difference between delegation and inheritance?
Delegation is an alternative to inheritance for reusing code among multiple classes. Inheritance uses the IS-A relationship for re-use; delegation uses the HAS-A reference relationship to do the same. Inheritance and delegation have the same kind of relationship that, say, Aspirin and Tylenol, have.
What is difference between delegate and protocol?
We can say Protocol as a set of rules. That rules can be optional or required like we have to use in protocol. Delegates is a message passing technique in objective C and swift. An object has to take care of that message.
Why is delegation better than inheritance?
The primary advantage of delegation is run-time flexibility – the delegate can easily be changed at run-time. But unlike inheritance, delegation is not directly supported by most popular object-oriented languages, and it doesn’t facilitate dynamic polymorphism.
What is C++ delegate?
A delegate is a class that wraps a pointer or reference to an object instance, a member method of that object’s class to be called on that object instance, and provides a method to trigger that call.
What is a identifier delegate?
Type Identifier. Delegates are configured to apply to specific object types. A type identifier identifies a business object type supported by a repository type.
Why is delegate type-safe?
A delegate is a type-safe function pointer that can reference a method that has the same signature as that of the delegate. You can take advantage of delegates in C# to implement events and call-back methods.
Delegation is simply passing a duty off to someone/something else. Delegation can be an alternative to inheritance. Delegation means that you use an object of another class as an instance variable, and forward messages to the instance.
When do you use delegation in a program?
Delegation is used in terms of responsibility. When we need to do something, we can delegate this responsibility to another object. It is usually contrasted to dispatching or forwarding. Based on delegation idea, Delegation Pattern was born.
When to use delegation instead of inheritance in OOP?
Delegation is a behavior. Inheritance is a model technique. Inheritance is for modeling “is-a”. A computer “is-a” electronic system.
Which is an example of a delegation pattern?
In Delegation Pattern, class composes delegate as a read-only property and passes calls of some methods to it. Here is an example: This is an example of Delegation pattern. Let’s see how we can use inheritance instead: