How to get interface basetype via reflection?

Question

public interface IBar {} 
public interface IFoo : IBar {}

typeof(IFoo).BaseType == null

How can I get IBar?

Answer 1

An interface is not a base type. Interfaces are not part of the inheritance tree.

To get access to interfaces list you can use:

typeof(IFoo).GetInterfaces()

or if you know the interface name:

typeof(IFoo).GetInterface("IBar")

If you are only interested in knowing if a type is implicitly compatible with another type (which I suspect is what you are looking for), use type.IsAssignableFrom(fromType). This is equivalent of 'is' keyword but with runtime types.

Example:

if(foo is IBar) {
    // ...
}

Is equivalent to:

if(typeof(IBar).IsAssignableFrom(foo.GetType())) {
    // ...
}

But in your case, you are probably more interested in:

if(typeof(IBar).IsAssignableFrom(typeof(IFoo))) {
    // ...
}