Remove list items where property = myValue

Question

I've got a problem. I have a list of objects (vehicle).

List<Vehicle> vehicleList = Vehicle.GetVehiclesFromDatabase();

And now I want something like this:

vehicleList.Remove(where vehicleList.Brand == "Volkswagen");

I hope I could explain what my problem is.

Many thanks in advance!

Possible duplicate of [c# remove item from list](http://stackoverflow.com/questions/10018957/c-sharp-remove-item-from-list) — raidensan, Apr 21 '16 at 09:39
Try something like this : List results = vehicleList.Where(x => vehicleList.Brand != "Volkswagen").ToList(); — jdweng, Apr 21 '16 at 09:40
Use `vehicleList.RemoveAll(item => item.Brand == "Volkswagen");` to remove all items with Volkswagen brand. To remove a single item you need to either pass the item, or know its index. — raidensan, Apr 21 '16 at 09:41

Alexander Derck · Accepted Answer · 2016-04-21T09:44:41.590

3

You can use List<T>.RemoveAll:

int recordsRemoved = vehicleList.RemoveAll(v => v.Brand == "Volkswagen");

The method takes a Predicate<T> (= Func<T,bool>), which will remove all items for which the predicate returns true.

For you this is equal to the following method:

bool Filter(Vehicle vehicle)
{
   return vehicle.Brand == "Volkswagen";
}

edited Apr 21 '16 at 09:44

answered Apr 21 '16 at 09:41

Alexander Derck

13,818
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1

This will remove all where the brand **isn't** Volkswagen, they want the opposite – Alfie Goodacre Apr 21 '16 at 09:44
Thank you a lot! It's exactly what I needed :) – BattlePumpkin Apr 21 '16 at 09:59

score 2 · Answer 2 · answered Apr 21 '16 at 09:40

2

You can use linq to do this, like so

vehicleList = vehicleList.Where(v => v.Brand != "Volkswagen").ToList();

You can also do this with a RemoveAll

vehicleList.RemoveAll(v => v.Brand == "Volkswagen");

answered Apr 21 '16 at 09:40

Alfie Goodacre

2,753
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Vikram Bose · Answer 3 · 2016-04-21T12:53:51.107

You can do like this

var itemToRemove = vehicleList.Single(r => r.Brand ==  "Volkswagen");
resultList.Remove(itemToRemove);

When you are not sure the item really exists you can use SingleOrDefault. SingleOrDefault will return null if there is no item (Single will throw an exception when it can't find the item). Both will throw when there is a duplicate value (two items with the same id).

var itemToRemove = vehicleList.SingleOrDefault(r => r.Brand ==  "Volkswagen");
if (itemToRemove != null)
    resultList.Remove(itemToRemove);

Remove list items where property = myValue

3 Answers3