泛型实现二分查找

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   //查询算法：二分查找
        /// <summary>
        ///查询算法：二分查找
        /// </summary>
        /// <param name="listObj">待查询的对象集合</param>
        /// <param name="pkid">查询关键字</param>
        /// <returns>返回关键字在集合中的位置</returns>
        public static int binarySearch<TObject>(List<TObject> listObj, int pkid)
        {
            int pos = -1;
            int low, high, mid;
            int PKID;
            if (listObj.Count > 1)
            {
                low = 0;
                high = listObj.Count - 1;
                mid = (low + high) / 2;

                while (low <= high)
                {
                    PKID = (int)typeof(TObject).GetProperty("pkid").GetValue(listObj[mid], null);

                    if (PKID == pkid)
                    {
                        pos = mid;
                        break;
                    }
                    else if (PKID > pkid)
                    {
                        high = mid - 1;
                        mid = (low + high) / 2;
                    }
                    else
                    {
                        low = mid + 1;
                        mid = (low + high) / 2;
                    }

                }
            }
            else if (listObj.Count == 1)
            {
                PKID = (int)typeof(TObject).GetProperty("pkid").GetValue(listObj[0], null);
                if (PKID == pkid)
                {
                    pos = 0;
                }
            }
            else
            {
                pos = -1;
            }

return pos;

}