Intersect LINQ query

Question

If I have an IEnumerable where ClassA exposes an ID property of type long. Is it possible to use a Linq query to get all instances of ClassA with ID belonging to a second IE

Answer 1

I've been tripping up all morning on Intersect, and how it doesn't work anymore in core 3, due to it being client side not server side.

From a list of items pulled from a database, the user can then choose to display them in a way that requires children to attached to that original list to get more information.

What use to work was:

itemList = _context.Item
        .Intersect(itemList)
        .Include(i => i.Notes)
        .ToList();

What seems to now work is:

itemList = _context.Item
        .Where(item => itemList.Contains(item))
        .Include(i => i.Notes)
        .ToList();

This seems to be working as expected, without any significant performance difference, and is really no more complicated than the first.