Question

The following obviously will not compile, so what should I change?

public bool IsFoobar(bool foo, bool bar)
{
    return db.Foobars.SingleOrDefault(fb => ((fb.foo == foo) && (fb.bar == bar)));
}

Answer 1

Try

public bool IsFoobar(bool foo, bool bar)
{
    return db.Foobars.Any(fb => fb.foo == foo && fb.bar == bar);
}