What is Function polymorphism and Class Polymorphism ? Difference ? Why we need it ?

Function polymorphism is a kind of overloading and overriding. Class polymorphism is like inheriting parent class / interface and instantiating the subclass with parent class / interface.

Runtime polymorphism - overriding
Compile time polymorphism - overloading

You can have a look at following article for more details.
http://www.dotnetfunda.com/articles/article258.aspx
http://www.dotnetfunda.com/articles/article505-what-is-polymorphism-.aspx

Hope this help.

Thank you.

Nav234, if this helps please login to Mark As Answer. | Alert Moderator

I believe that both overriding & overloading are compite time polymorphism as when we compile the application it knows which method to call in case of overriding.
so what I think is that runtime time polymorphism is when we use interface/abstract class with the similar behaviour and pass/use that interface in other classes (e.g. through depedancy injecttion, inversion of control) and that class only knows about the behaviour/interface but dont know the exact object at compile time and only knows at runtime.

Nav234, if this helps please login to Mark As Answer. | Alert Moderator

I believe that both overriding & overloading are compite time polymorphism as when we compile the application it knows which method to call in case of overriding.
so what I think is that runtime time polymorphism is when we use interface/abstract class with the similar behaviour and pass/use that interface in other classes (e.g. through depedancy injecttion, inversion of control) and that class only knows about the behaviour/interface but dont know the exact object at compile time and only knows at runtime.

Nav234, if this helps please login to Mark As Answer. | Alert Moderator