How can it be that PageContent implements IAddChild but has none of IAddChild interface methods?

Question

The PageContent element implements IAddChild but doesn't implements IAddChild methods so I can't call AddChild method on PageContent.. How can it be?
And if i cast PageContent to IAddChild i can call AddChild method on it - So it does implement it somewhere...

I am confused with this behavior. Can someone shed some light on this?

Answer 1

Explicit interface implementation :

• http://msdn.microsoft.com/en-us/library/ms173157.aspx
• http://msdn.microsoft.com/en-us/library/aa288461.aspx

Answer 2

The methods are implemented explicitly for the interface. That means that you can only reach them using a reference of the interface type, not using a reference of the class type.

This is usually done when the methods make sense when you use the object through the interface, but not as much for the object itself.