Check if multiple values (stored in a dedicated collection) are in a LINQ collection, in query

Question

What is the method in LINQ to supply a collection of values and check if any/all of these values are in a collection?

Thanks

Answer 1

You can emulate this via .Intersect() and check if the intersection set has all the required elements. I guess this is pretty inefficient but quick and dirty.

List<T> list = ...
List<T> shouldBeContained = ...
bool containsAll = (list.Intersect(shouldBeContained).Count == shouldBeContained.Count)

Or you could do it with .All(). I guess this is more efficient and cleaner:

List<T> list = ...
List<T> shouldBeContained = ...
bool containsAll = (shouldBeContained.All(x=>list.Contains(x));