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    <blockquote> <p>Please tell me whether the following code will complie or not?</p> </blockquote> <p>Yes, it will - but you could have found that out for yourself just by trying it.</p> <blockquote> <p>Why it is so?</p> </blockquote> <p>Quite simply, <code>Derived</code> implements the contract required by <code>MyInterface</code>. It happens to do that via <code>Base</code> which is unaware of the interface, but it still has all the relevant members.</p> <p>There's a danger here, though - in reality, interfaces are about more than just having appropriate members available for callers; they're about the <em>semantics</em> of those members. A class hierarchy like this only works when the semantics of <code>Base.Method()</code> exactly match the requirements of <code>MyInterface.Method()</code> <em>by coincidence</em> (as opposed to by explicit, declared design). Even if it's valid to start with, the maintainer of <code>Base</code> may decide to make a change to the behaviour of <code>Method</code> which is valid according to what <code>Base.Method</code> has guaranteed, but <em>isn't</em> valid according to what the interface guarantees.</p> <p>EDIT: In terms of the language specification, this is in section 13.4.4 of the C# 4 spec:</p> <blockquote> <p>A class or struct must provide implementations of all members of the interfaces that are listed in the base class list of the class or struct. The process of locating implementations of interface members in an implementing class or struct is known as interface mapping.</p> <p>Interface mapping for a class or struct C locates an implementation for each member of each interface specified in the base class list of C. The implementation of a particular interface member I.M, where I is the interface in which the member M is declared, is determined by examining each class or struct S, starting with C and repeating for each successive base class of C, until a match is located.</p> <p>[...]</p> <p>A compile-time error occurs if implementations cannot be located for all members of all interfaces specified in the base class list of C. </p> </blockquote>
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    1. POinterface with base class and derived class to achieve multiple inheritance
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    1. COThanks!!!!! I compiled and checked it already but i just want to know how those derived class works with the interface.
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      1. USVignesh Lakshmanan
    2. CO@VigneshLakshmanan: If you'd compiled it already, why did you explicitly ask whether it compiled? If you'd said: "This code compiles, but I don't understand why" that would have been a far more sensible question.
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    3. COI am Sorry about that!!!!!!!! I had a doubt like why it is compiling and i am not sure of it why also? thats why i have asked question will it compile?
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