Generic and Iterator

[siavoshkc]

class EventAwareList<T> : System.Collections.Generic.List<T> 
{
    public delegate void ListHandler(object sender , EventAwareList<T>.ListEventArgs<T> e);
    public event ListHandler AddEvent;

   

    public class ListEventArgs<U> : EventArgs
    {
        public int index;
        public U value;
    }
    


    public new void Add(T item)
    {
        base.Add(item);
        if (AddEvent != null)
        {
            ListEventArgs<T> addevArgs = new ListEventArgs<T>();
            addevArgs.value = item;
            addevArgs.index = base.Count - 1;
            AddEvent(this, addevArgs);
        }
    }

    public new T this[int i]
    {

        get
        {
            return base[i];

        }

        set
        {
            base[i] = value;
            if (AddEvent != null)
            {
                ListEventArgs<T> addevArgs = new ListEventArgs<T>();
                addevArgs.value = base[i];
                addevArgs.index = i;
                AddEvent(this, addevArgs);
            }
        }
    }

    public new System.Collections.Generic.IEnumerable<T> GetEnumerator()
    {
        
        for(int i = 0; i < base.Count ;++i)
        {
            
            yield return base[i];
        }
    }

}

In this class I have an iterator.
It works like this:

EventAwareList<int> el = new EventAwareList<int>();
        
        el.Add(2);
        el.Add(43);
        System.Collections.Generic.List<int> s;
   
        foreach (int i in el.GetEnumerator())
        {
            Console.WriteLine(i);
        }

But I see that you can write foreach(int i in el), but how?

[CornedBee]

You should be wondering why your GetEnumerator has the new keyword. The solution to your problem lies there.

IEnumerable.GetEnumerator (as the name says) returns an IEnumerator, not an IEnumerable. Make this change, and you can use the list directly in the foreach.

[siavoshkc]

You should be wondering why your GetEnumerator has the new keyword. The solution to your problem lies there.

I know why. Because it is defined in the base class.
I wanted to add this:

IEnumerator IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }

But it generates an error:Error 1 'EventAwareList<T>.IEnumerable.GetEnumerator()': containing type does not implement interface 'System.Collections.IEnumerable'

[edit]
This error means that my class does not implemented IEnumerable. But I thought it should be inherited from the base class.

[siavoshkc]

OK, I made it IEnumerator and it worked.
Thanks a LOT CornedBee.