Can Interfaces be a substitute for Multiple Inheritance in C#?
EDIT: This is a duplicate of: https://stackoverflow.com/questions/579090/why-c-doesnt-support-multiple-inheritence-can-interfaces-be-used-as-a-substi
Which was a duplicate of: Should C# have multiple inheritance?
Multiple inheritance implies that you inherit functionality from multiple base classes. Since interfaces define interfaces, not implementations, the answer is no.
To some extent, yes. The classic "is-a" relationship that inheritance provides can be expanded with the use of interfaces. Meaning, if a class inherits from another class, and implements 3 interfaces, an object of this class can be passed into a method that takes the base class, or any of the three interfaces as parameters. So, in a sense, this class "is-a" one of 4 different things. Makes sense?
Conceptually, interfaces can allow you to have multiple is-a relationships with other categories of classes. This is part of why multiple inheritance is used.
For example,
public class TradeReport : IReport, ITrade, IComplianceRecord
Provided the class above implements the methods of all three interfaces meaningfully, you can use it to describe a report, a trade, and a compliance record.
But, that's the limit. There's no implementation inheritance in interfaces.
