C:/Private/OSS/n2cms/github/n2cms/src/Framework/N2/Collections/CountFilter.cs

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using System;
using System.Collections.Generic;
using System.Text;

namespace N2.Collections
{
        public class CountFilter : ItemFilter
        {
                #region Constructors



                public CountFilter(int startIndex, int maxCount)
                {
                        this.startIndex = startIndex;
                        this.maxCount = maxCount > 0 ? maxCount : int.MaxValue;
                } 
                #endregion

                #region Private Members
                private int startIndex;
                private int maxCount;
                private int currentIndex; 
                #endregion

                #region Properties
                public int StartIndex
                {
                        get { return startIndex; }
                        set { startIndex = value; }
                }

                public int MaxCount
                {
                        get { return maxCount; }
                        set { maxCount = value; }
                }

                public int CurrentIndex
                {
                        get { return currentIndex; }
                        set { currentIndex = value; }
                } 
                #endregion

                #region Methods
                public override void Filter(IList<ContentItem> items)
                {
                        while (items.Count > maxCount + startIndex)
                                items.RemoveAt(items.Count - 1);
                        while (items.Count > maxCount)
                                items.RemoveAt(0);
                }

                public override bool Match(ContentItem item)
                {
                        return Match(CurrentIndex++);
                }

                public virtual bool Match(int itemIndex)
                {
                        return itemIndex >= StartIndex 
                                && (MaxCount == int.MaxValue || itemIndex < (StartIndex + MaxCount));
                }

                public virtual void Reset()
                {
                        CurrentIndex = 0;
                } 
                #endregion

                #region Static Methods
                public static void Filter(IList<ContentItem> items, int startIndex, int maxCount)
                {
                        ItemFilter.Filter(items, new CountFilter(startIndex, maxCount));
                }
                #endregion

                #region IDisposable Members

                public override void Dispose()
                {
                        Reset();
                }

                #endregion
        }
}