using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var numbers=new[]{1,2,3,4,5};

        var eg = numbers.Slice(-3,-1);

        foreach (var i in eg)

        {

            Console.Write("{0}, ", i);

        }

        Console.WriteLine();    // Output: 3, 4,

​

    }

}

​

public static class Extensions

{

        /// <summary>

        /// Slices the specified collection like Python does

        /// </summary>

        /// <typeparam name="T"></typeparam>

        /// <param name="me">the collection</param>

        /// <param name="start">The start point.</param>

        /// <param name="end">The end point.</param>

        /// <returns></returns>

        /// <example><code>

        /// var numbers=new[]{1,2,3,4,5};

        /// var eg = numbers.Slice(-3,-1);

        /// foreach (var i in eg)

        /// {

        ///     Console.Write("{0}, ", i);

        /// }

        /// Console.Writeline();    // Output: 3, 4,</code></example>

        /// <exception cref="System.ArgumentException">starting point must be less than or equal to ending point;start</exception>

        public static IEnumerable<T> Slice<T>(this IEnumerable<T> me, int? start = null, int? end = null)

        {

            if (start.HasValue && end.HasValue && start.Value > end.Value)

            {

                throw new ArgumentException("starting point must be less than or equal to ending point", "start");

            }

​

            if (start.HasValue && start < 0)

            {

                start = me.Count() + start;

            }

​

            if (end.HasValue && end < 0)

            {

                end = me.Count() + end;

            }

​

            if (!start.HasValue)

            {

                start = 0;

            }

​

            if (!end.HasValue)

            {

                end = me.Count();

            }

​

            return me.Skip(start.Value).Take(end.Value - start.Value);

        }

}