C# LINQ select from list
var eventids = GetEventIdsByEventDate(DateTime.Now);
var result = eventsdb.Where(e => eventids.Contains(e));
If you are returnning List<EventFeed>
inside the method, you should change the method return type from IEnumerable<EventFeed>
to List<EventFeed>
.
In likeness of how I found this question using Google, I wanted to take it one step further.
Lets say I have a string[] states
and a db Entity
of StateCounties
and I just want the states from the list returned and not all of the StateCounties
.
I would write:
db.StateCounties.Where(x => states.Any(s => x.State.Equals(s))).ToList();
I found this within the sample of CheckBoxList
for nu-get.
The "in" in Linq-To-Sql uses a reverse logic compared to a SQL query.
Let's say you have a list of integers, and want to find the items that match those integers.
int[] numbers = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
var items = from p in context.Items
where numbers.Contains(p.ItemId)
select p;
Anyway, the above works fine in linq-to-sql but not in EF 1.0. Haven't tried it in EF 4.0