Removing elements from binding list

c# wpf linq bindinglist
Rafay Zia Mir picture Rafay Zia Mir · Feb 8, 2012 · Viewed 15.1k times · Source

In one of my projects I'm trying to remove an item from a list where the id is equal to the given id.

I have a BindingList<T> called UserList.

Lists have all the method RemoveAll().

Since I have a BindingList<T>, I use it like that:

UserList.ToList().RemoveAll(x => x.id == ID )

However, my list contains the same number of items as before.
Why it's not working?

Answer

vc 74 picture vc 74 · Feb 8, 2012

It's not working because you are working on a copy of the list which you created by calling ToList().

BindingList<T> doesn't support RemoveAll(): it's a List<T> feature only, so:

IReadOnlyList<User> usersToRemove = UserList.Where(x => (x.id == ID)).
                                             ToList();

foreach (User user in usersToRemove)
{
    UserList.Remove(user);
}

We're calling ToList() here because otherwise we'll enumerate a collection while modifying it.

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