Question

what is the difference between explicit interface and implicit interface implementation in c#/asp.net? in which scenario we can use the explicit interface and implicit interface implementation.

Thanks,

Pradeep

Answer 1

Say you have two interfaces, IDoStuff<T> and IDoStuff, which your class implements. They both have a method “GetStuff”, but one has the signature T GetStuff(), and the other has the signature object GetStuff().

The problem is that .net will not let you have two methods named the same thing that only differ on the return type. But you need to have both of these methods in your class to satisfy both interfaces. If T is, in fact, an object, then you can use explicit implementation like so.

public T GetStuff()
{
  T stuff;
  //Stuff Is Got
  return stuff;
}

IDoStuff.GetStuff()
{
  return (object)GetStuff();
}

Note that because IDoStuff mandates the security requirements of GetStuff, IDoStuff.GetStuff will be public/private/protected/internal based on that interface’s declaration.

If you wanted, you could do every implantation explicitly, but the full method name for each would be InterfaceName.MethodName, and that gets a little annoying to read and write. Usually this is only used when you want to implement a method with the same signature multiple times to satisfy several interfaces.