Comment Inheritance for C# (actually any language)

You can always use the <inheritdoc /> tag:

public class Foo : IFoo
{
    /// <inheritdoc />
    public void Foo() { ... }
    /// <inheritdoc />
    public void Bar() { ... }
    /// <inheritdoc />
    public void Snafu() { ... }
}

Using the cref attribute, you can even refer to an entirely different member in an entirely different class or namespace!

public class Foo
{
    /// <inheritdoc cref="System.String.IndexOf" />
    public void Bar() { ... } // this method will now have the documentation of System.String.IndexOf
}

Use /// <inheritdoc/> if you want inheritance. Avoid GhostDoc or anything like that.

I agree it is annoying that comments are not inherited. It would be a fairly simple add-in to create if someone had the time (i wish i did).

That said, in our code base we put XML comments on the interfaces only and add extra implementation comments to the class. This works for us as our classes are private/internal and only the interface is public. Any time we use the objects via the interfaces we have full comments display in intellisence.

GhostDoc is good start and has made the process easier to write comments. It is especially useful keeping comments up-to-date when you add/remove parameters, re-run GhostDoc and it will update the description.

GhostDoc does exactly that. For methods which aren't inherited, it tries to create a description out of the name.

FlingThing() becomes "Flings the Thing"