Comparison : interface methods vs virtual methods vs abstract methods

[Origin]: http://stackoverflow.com/questions/4762930/comparison-interface-methods-vs-virtual-methods-vs-abstract-methods

What are the advantages and disadvantages of each of these?

  • interface methods
  • virtual methods
  • abstract methods

When one should choose what? What are the points one should keep in mind when making this decision?

shareedit

Virtual and abstract are almost the same. A virtual method has an implementation in the base class that can optionally be overridden, while an abstract method hasn’t and must be overridden in a child class. Otherwise they are the same. Choosing between them depends on the situation. If you got a base implementation, you use virtual. If you don’t, and you need every descendant to implement it for itself, you choose abstract.

Interface methods are implementations of a method that is declared in an interface that the class implements. This is quite unrelated to the other two. I think a method can be both virtual and interface. The advantage of interfaces is that you declare one interface (duh) that can be implemented by two totally different classes. That way, you can run the same code on two different classes, as long as the methods you’d like to call are declared in an interface they share.

shareedit
Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s