使用 LINQ，如何查看包含在另一个对象/列表中的列表？

Question

Say I have IEnumOfFood that contains a food object that lists out each ingredient. So something like IEnumOfFood[0] would be {'Celery', 'Onion', 'Chicken', [Stock]}. In this case, [Stock] is another IEnumerable. I'm trying to get each element in IEnumOfFood where Stock.Herb == "Bay Leaf". It seems that no matter how I try and reword the LINQ query it always has some sort of error. Currently I have this:

IEnumOfFood= IEnumFoodItems.Select(x => x.Select(
y => y.Stock.Where(
y => y.Herb == "BayLeaf")));

Which throws a 'Cannot convert lambda expression to type 'bool' because it is not a delegate type'. This is just one of the many ways I've tried to get an element of IEnumOfFood where the Stock Enum has herb as 'Bay Leaf', I'm not saying this is what should work.

Answer 1

Have you tryed:

IEnumFoodItems.Where(x => x.Any(s => s.Stock.Any(h => h.Herb == "BayLeaf")))