implicit operator using interfaces

Solution 1:

The reason you can't do this is because it is specifically forbidden in the C# language specification:

Source: ECMA-334 Section 15.10.4

A class or struct is permitted to declare a conversion from a source type S to a target type T provided all of the following are true:

• ...
• Neither S nor T is object or an interface-type.

and

User-defined conversions are not allowed to convert from or to interface-types. In particular, this restriction ensures that no user-defined transformations occur when converting to an interface-type, and that a conversion to an interface-type succeeds only if the object being converted actually implements the specified interface-type.