Question

If we have a class that inherits from multiple interfaces, and the interfaces have methods with the same name, how can we implement these methods in my class? How can we specify which method of which interface is implemented?

Answer 1

By implementing the interface explicitly, like this:

public interface ITest {
    void Test();
}
public interface ITest2 {
    void Test();
}
public class Dual : ITest, ITest2
{
    void ITest.Test() {
        Console.WriteLine("ITest.Test");
    }
    void ITest2.Test() {
        Console.WriteLine("ITest2.Test");
    }
}

When using explicit interface implementations, the functions are not public on the class. Therefore in order to access these functions, you have to first cast the object to the interface type, or assign it to a variable declared of the interface type.

var dual = new Dual();
// Call the ITest.Test() function by first assigning to an explicitly typed variable
ITest test = dual;
test.Test();
// Call the ITest2.Test() function by using a type cast.
((ITest2)dual).Test();