Filter IEnumerable against IEnumerable

Question

I have an object Style with a property StockNumber. I would like to filter a list of all Db.Styles against an IEnumerable

Answer 1

You can think of Intersect as effectively a Join where the keys of each object are always "themselves". Here you want to perform a join where the key isn't always "itself", so you use a Join (or, if you need to remove duplicates, a GroupJoin).

var query = from style in Db.Styles
    join number in stockNumbers
    on style.StockNumber equals number
    into numbers
    where numbers.Any()
    select style;