public class NeEntityComparer : IComparer
     
          {        public int Compare(NeEntity x, NeEntity y)        {            if (x == null)            {                if (y == null)                {                    // If x is null and y is null, they're                    // equal.                     return 0;                }                else                {                    // If x is null and y is not null, y                    // is greater.                     return -1;                }            }            else            {                // If x is not null...                //                if (y == null)                // ...and y is null, x is greater.                {                    return 1;                }                else                {                    // ...and y is not null, compare the                     // lengths of the two strings.                    //                    int retval = x.NeID.CompareTo(y.NeID);                    return retval;                }            }        }    }