Thread: C# Lists - can I override Add() ?

Originally Posted by theoobe

One option available to you is inheriting the List class and then using "new" to override the Add method. I think something like this would work:

Code:

    class CustomList<T> : List<T>
    {
        public new void Add(T obj)
        {
            if (base.Count < 10) // or whatever limit
                base.Add(obj);
        }
    }

Not really. Anything that uses List<T> instead of CustomList<T> will use List<T>.Add, which isn't really what you're intending. Instead, you might have a private List<T> and implement the IList<T> interface with a lot of jump code, inserting your custom Add logic in IList<T>.Add.

Alternately, if you're not bound to List<T>, you can use Collection<T> and override InsertItem.

Originally Posted by gah_ribaldi

...so that it refuses to add more elements to a list once the list's capacity has been reached.

If you know your capacity, why use a List at all? Why not just use an array?