public static class PinYinHelper
    {
        /// <summary> 
        /// 汉字转化为拼音
        /// </summary> 
        /// <param name="str">汉字</param> 
        /// <returns>全拼</returns> 
        public static string GetPinyin(string str)
        {
            var result = "";
            if (!string.IsNullOrEmpty(str))
            {
                result = NPinyin.Pinyin.GetPinyin(str)?.Replace(" ", "").ToLower();
            }
            return result;
        }

        /// <summary> 
        /// 汉字转化为拼音首字母
        /// </summary> 
        /// <param name="str">汉字</param> 
        /// <returns>首字母</returns> 
        public static string GetInitials(string str)
        {
            var result = "";
            if (!string.IsNullOrEmpty(str))
            {
                result = NPinyin.Pinyin.GetInitials(str)?.Trim().ToLower();
            }
            return result;
        }

    }