获取简单汉字、字母数字字符串的首字母

        #region 取得一个汉字的拼音首字母
        /// <summary>
        /// 取得一个汉字的拼音首字母
        /// </summary>
        /// <param name="cnChar">一个汉字</param>
        /// <returns>首字母</returns>
        private string GetSpell(string cnChar)
        {
            byte[] arrCN = Encoding.Default.GetBytes(cnChar);
            if (arrCN.Length > 1)
            {
                int area = (short)arrCN[0];
                int pos = (short)arrCN[1];
                int code = (area << 8) + pos;
                int[] areacode = { 45217, 45253, 45761, 46318, 46826, 47010, 47297, 47614, 48119, 48119, 49062, 49324, 49896, 50371, 50614, 50622, 50906, 51387, 51446, 52218, 52698, 52698, 52698, 52980, 53689, 54481 };
                for (int i = 0; i < 26; i++)
                {
                    int max = 55290;
                    if (i != 25) max = areacode[i + 1];
                    if (areacode[i] <= code && code < max)
                    {
                        return Encoding.Default.GetString(new byte[] { (byte)(65 + i) }).ToUpper();
                    }
                }
                return "*";
            }
            else return cnChar;
        }

        #endregion


        #region 获取名称首字母
        /// <summary>
        /// 获取名称首字母
        /// </summary>
        /// <returns></returns>
        private string GetFirstCode(string codestr)
        {
            string code = GetSpell(codestr);
            if (code == "*")
            {
                code = txtrealname.Text.ToString().Substring(0, 1).ToUpper();
            }
            if (code == "1")
            {
                code = "Y";
            }
            else if (code == "2")
            {
                code = "E";
            }
            else if (code == "3" || code == "4")
            {
                code = "S";
            }
            else if (code == "5")
            {
                code = "E";
            }
            else if (code == "6" || code == "0")
            {
                code = "L";
            }
            else if (code == "7")
            {
                code = "Q";
            }
            else if (code == "8")
            {
                code = "B";
            }
            else if (code == "9")
            {
                code = "J";
            }
            return code;
        }
        #endregion