AceEnumerator.cs

using System.Collections;

namespace System.Security.AccessControl
{
    public sealed class AceEnumerator : IEnumerator
    {
        private int _current;

        private readonly GenericAcl _acl;

        object IEnumerator.Current
        {
            get
            {
                if (_current == -1 || _current >= _acl.Count)
                {
                    throw new InvalidOperationException(Environment.GetResourceString("Arg_InvalidOperationException"));
                }
                return _acl[_current];
            }
        }

        public GenericAce Current => ((IEnumerator)this).Current as GenericAce;

        internal AceEnumerator(GenericAcl collection)
        {
            if (collection == null)
            {
                throw new ArgumentNullException("collection");
            }
            _acl = collection;
            Reset();
        }

        public bool MoveNext()
        {
            _current++;
            return _current < _acl.Count;
        }

        public void Reset()
        {
            _current = -1;
        }
    }
}