自定义两对象是否相等方法，必须用到GetHashCode方法，如

public class AirspaceCompareByUUID : IEqualityComparer<AIRSPACE_TS>

    {

        public bool Equals(AIRSPACE_TS x, AIRSPACE_TS y)

        {

            if (x == null || y == null)

                return false;

            if (x.AIRSPACE_UUID == y.AIRSPACE_UUID)

                return true;

            else

                return false;

        }

        public int GetHashCode(AIRSPACE_TS obj)

        {

            if (obj == null)

                return 0;

            else

                return obj.AIRSPACE_UUID.GetHashCode();

        }

    }