输入汉字字符串索引拼音的首字母

在做项目的时候，输入客户的名字，为了方便索引汉字字符串的拼音首字母，作助记码，于是到网上找了一下，还好，有个单个汉字的处理！

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace WinMarket
{
    /// <summary>
    /// Classfun 的摘要说明。
    /// </summary>
    public class Classfun
    {
        private string Capstr;

        public Classfun()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }
        public string ChineseCap(string ChineseStr)
        {


            byte[] ZW = new byte[2];
            long ChineseStr_int;
            string CharStr, ChinaStr = "";
            for (int i = 0; i <= ChineseStr.Length - 1; i++)
            {
                CharStr = ChineseStr.Substring(i, 1).ToString();
                ZW = System.Text.Encoding.Default.GetBytes(CharStr);
                // 得到汉字符的字节数组
                if (ZW.Length == 2)
                {
                    int i1 = (short)(ZW[0]);
                    int i2 = (short)(ZW[1]);
                    ChineseStr_int = i1 * 256 + i2;
                    //table of the constant list
                    // 'A'; //45217..45252
                    // 'B'; //45253..45760
                    // 'C'; //45761..46317
                    // 'D'; //46318..46825
                    // 'E'; //46826..47009
                    // 'F'; //47010..47296
                    // 'G'; //47297..47613

                    // 'H'; //47614..48118
                    // 'J'; //48119..49061
                    // 'K'; //49062..49323
                    // 'L'; //49324..49895
                    // 'M'; //49896..50370
                    // 'N'; //50371..50613
                    // 'O'; //50614..50621
                    // 'P'; //50622..50905
                    // 'Q'; //50906..51386

                    // 'R'; //51387..51445
                    // 'S'; //51446..52217
                    // 'T'; //52218..52697
                    //没有U,V
                    // 'W'; //52698..52979
                    // 'X'; //52980..53640
                    // 'Y'; //53689..54480
                    // 'Z'; //54481..55289

                    if ((ChineseStr_int >= 45217) && (ChineseStr_int <= 45252))
                    {
                        ChinaStr = "A";
                    }
                    else if ((ChineseStr_int >= 45253) && (ChineseStr_int <= 45760))
                    {
                        ChinaStr = "B";
                    }
                    else if ((ChineseStr_int >= 45761) && (ChineseStr_int <= 46317))
                    {
                        ChinaStr = "C";

                    }
                    else if ((ChineseStr_int >= 46318) && (ChineseStr_int <= 46825))
                    {
                        ChinaStr = "D";
                    }
                    else if ((ChineseStr_int >= 46826) && (ChineseStr_int <= 47009))
                    {
                        ChinaStr = "E";
                    }
                    else if ((ChineseStr_int >= 47010) && (ChineseStr_int <= 47296))
                    {
                        ChinaStr = "F";
                    }
                    else if ((ChineseStr_int >= 47297) && (ChineseStr_int <= 47613))
                    {
                        ChinaStr = "G";
                    }
                    else if ((ChineseStr_int >= 47614) && (ChineseStr_int <= 48118))
                    {

                        ChinaStr = "H";
                    }

                    else if ((ChineseStr_int >= 48119) && (ChineseStr_int <= 49061))
                    {
                        ChinaStr = "J";
                    }
                    else if ((ChineseStr_int >= 49062) && (ChineseStr_int <= 49323))
                    {
                        ChinaStr = "K";
                    }
                    else if ((ChineseStr_int >= 49324) && (ChineseStr_int <= 49895))
                    {
                        ChinaStr = "L";
                    }
                    else if ((ChineseStr_int >= 49896) && (ChineseStr_int <= 50370))
                    {
                        ChinaStr = "M";
                    }

                    else if ((ChineseStr_int >= 50371) && (ChineseStr_int <= 50613))
                    {
                        ChinaStr = "N";

                    }
                    else if ((ChineseStr_int >= 50614) && (ChineseStr_int <= 50621))
                    {
                        ChinaStr = "O";
                    }
                    else if ((ChineseStr_int >= 50622) && (ChineseStr_int <= 50905))
                    {
                        ChinaStr = "P";

                    }
                    else if ((ChineseStr_int >= 50906) && (ChineseStr_int <= 51386))
                    {
                        ChinaStr = "Q";

                    }

                    else if ((ChineseStr_int >= 51387) && (ChineseStr_int <= 51445))
                    {
                        ChinaStr = "R";
                    }
                    else if ((ChineseStr_int >= 51446) && (ChineseStr_int <= 52217))
                    {
                        ChinaStr = "S";
                    }
                    else if ((ChineseStr_int >= 52218) && (ChineseStr_int <= 52697))
                    {
                        ChinaStr = "T";
                    }
                    else if ((ChineseStr_int >= 52698) && (ChineseStr_int <= 52979))
                    {
                        ChinaStr = "W";
                    }
                    else if ((ChineseStr_int >= 52980) && (ChineseStr_int <= 53640))
                    {
                        ChinaStr = "X";
                    }
                    else if ((ChineseStr_int >= 53689) && (ChineseStr_int <= 54480))
                    {
                        ChinaStr = "Y";
                    }
                    else if ((ChineseStr_int >= 54481) && (ChineseStr_int <= 55289))
                    {
                        ChinaStr = "Z";
                    }

                }
                else
                {
                    Capstr = ChineseStr;
                    break;
                }

                Capstr = Capstr + ChinaStr;
            }



            return Capstr;

        }


    }
}