获取字符串的首字母(包括中文),应用于按26个字母过滤和排序!

   公司的项目中要实现按26个字母过滤出相应的字段并且要区分多语言,一般来说拉丁字母很好,可是象中文这样的就不太好弄了,后来经过同事的帮忙在网上找了一些代码,能实现根据首字母过滤中文,现贴于下,做个记号.

核心处理类

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Text;

namespace WebApplication1
{
    public class GetAlphaFirst
    {
        public GetAlphaFirst()
        {

        }

        /**//**/
        /**//// <summary>
        /// 获得给定字符串的首字母
        /// </summary>
        /// <param name="IndexTxt">需要获得的字符串</param>
        /// <returns></returns>
        public string GetIndexCode(string indexTxt)
        {
            return IndexCode(indexTxt);
        }
        //返回给定字符串的首字母
        private String IndexCode(String IndexTxt)
        {
            String _Temp = null;
            for (int i = 0; i < IndexTxt.Length; i++)
                _Temp = _Temp + GetOneIndex(IndexTxt.Substring(i, 1));
            return _Temp;
        }

        //得到单个字符的首字母
        private String GetOneIndex(String OneIndexTxt)
        {
            if (Convert.ToChar(OneIndexTxt) >= 0 && Convert.ToChar(OneIndexTxt) < 256)
                return OneIndexTxt;
            else
            {
                Encoding gb2312 = Encoding.GetEncoding("gb2312");
                byte[] unicodeBytes = Encoding.Unicode.GetBytes(OneIndexTxt);
                byte[] gb2312Bytes = Encoding.Convert(Encoding.Unicode, gb2312, unicodeBytes);
                return GetX(Convert.ToInt32(String.Format("{0:D2}", Convert.ToInt16(gb2312Bytes[0]) - 160) + String.Format("{0:D2}", Convert.ToInt16(gb2312Bytes[1]) - 160)));
            }

        }

        //根据区位得到首字母
        private String GetX(int GBCode)
        {
            if (GBCode >= 1601 && GBCode < 1637) return "A";
            if (GBCode >= 1637 && GBCode < 1833) return "B";
            if (GBCode >= 1833 && GBCode < 2078) return "C";
            if (GBCode >= 2078 && GBCode < 2274) return "D";
            if (GBCode >= 2274 && GBCode < 2302) return "E";
            if (GBCode >= 2302 && GBCode < 2433) return "F";
            if (GBCode >= 2433 && GBCode < 2594) return "G";
            if (GBCode >= 2594 && GBCode < 2787) return "H";
            if (GBCode >= 2787 && GBCode < 3106) return "J";
            if (GBCode >= 3106 && GBCode < 3212) return "K";
            if (GBCode >= 3212 && GBCode < 3472) return "L";
            if (GBCode >= 3472 && GBCode < 3635) return "M";
            if (GBCode >= 3635 && GBCode < 3722) return "N";
            if (GBCode >= 3722 && GBCode < 3730) return "O";
            if (GBCode >= 3730 && GBCode < 3858) return "P";
            if (GBCode >= 3858 && GBCode < 4027) return "Q";
            if (GBCode >= 4027 && GBCode < 4086) return "R";
            if (GBCode >= 4086 && GBCode < 4390) return "S";
            if (GBCode >= 4390 && GBCode < 4558) return "T";
            if (GBCode >= 4558 && GBCode < 4684) return "W";
            if (GBCode >= 4684 && GBCode < 4925) return "X";
            if (GBCode >= 4925 && GBCode < 5249) return "Y";
            if (GBCode >= 5249 && GBCode <= 5589) return "Z";
            if (GBCode >= 5601 && GBCode <= 8794)
            {
                String CodeData = "cjwgnspgcenegypbtwxzdxykygtpjnmjqmbsgzscyjsyyfpggbzgydywjkgaljswkbjqhyjwpdzlsgmr"
                                  + "ybywwccgznkydgttngjeyekzydcjnmcylqlypyqbqrpzslwbdgkjfyxjwcltbncxjjjjcxdtqsqzycdxxhgckbphffss"
                                  + "pybgmxjbbyglbhlssmzmpjhsojnghdzcdklgjhsgqzhxqgkezzwymcscjnyetxadzpmdssmzjjqjyzcjjfwqjbdzbjgd"
                                  + "nzcbwhgxhqkmwfbpbqdtjjzkqhylcgxfptyjyyzpsjlfchmqshgmmxsxjpkdcmbbqbefsjwhwwgckpylqbgldlcctnma"
                                  + "eddksjngkcsgxlhzaybdbtsdkdylhgymylcxpycjndqjwxqxfyyfjlejbzrwccqhqcsbzkymgplbmcrqcflnymyqmsqt"
                                  + "rbcjthztqfrxchxmcjcjlxqgjmshzkbswxemdlckfsydsglycjjssjnqbjctyhbftdcyjdgwyghqfrxwckqkxebpdjpx"
                                  + "jqsrmebwgjlbjslyysmdxlclqkxlhtjrjjmbjhxhwywcbhtrxxglhjhfbmgykldyxzpplggpmtcbbajjzyljtyanjgbj"
                                  + "flqgdzyqcaxbkclecjsznslyzhlxlzcghbxzhznytdsbcjkdlzayffydlabbgqszkggldndnyskjshdlxxbcghxyggdj"
                                  + "mmzngmmccgwzszxsjbznmlzdthcqydbdllscddnlkjyhjsycjlkohqasdhnhcsgaehdaashtcplcpqybsdmpjlpcjaql"
                                  + "cdhjjasprchngjnlhlyyqyhwzpnccgwwmzffjqqqqxxaclbhkdjxdgmmydjxzllsygxgkjrywzwyclzmcsjzldbndcfc"
                                  + "xyhlschycjqppqagmnyxpfrkssbjlyxyjjglnscmhcwwmnzjjlhmhchsyppttxrycsxbyhcsmxjsxnbwgpxxtaybgajc"
                                  + "xlypdccwqocwkccsbnhcpdyznbcyytyckskybsqkkytqqxfcwchcwkelcqbsqyjqcclmthsywhmktlkjlychwheqjhtj"
                                  + "hppqpqscfymmcmgbmhglgsllysdllljpchmjhwljcyhzjxhdxjlhxrswlwzjcbxmhzqxsdzpmgfcsglsdymjshxpjxom"
                                  + "yqknmyblrthbcftpmgyxlchlhlzylxgsssscclsldclepbhshxyyfhbmgdfycnjqwlqhjjcywjztejjdhfblqxtqkwhd"
                                  + "chqxagtlxljxmsljhdzkzjecxjcjnmbbjcsfywkbjzghysdcpqyrsljpclpwxsdwejbjcbcnaytmgmbapclyqbclzxcb"
                                  + "nmsggfnzjjbzsfqyndxhpcqkzczwalsbccjxpozgwkybsgxfcfcdkhjbstlqfsgdslqwzkxtmhsbgzhjcrglyjbpmljs"
                                  + "xlcjqqhzmjczydjwbmjklddpmjegxyhylxhlqyqhkycwcjmyhxnatjhyccxzpcqlbzwwwtwbqcmlbmynjcccxbbsnzzl"
                                  + "jpljxyztzlgcldcklyrzzgqtgjhhgjljaxfgfjzslcfdqzlclgjdjcsnclljpjqdcclcjxmyzftsxgcgsbrzxjqqcczh"
                                  + "gyjdjqqlzxjyldlbcyamcstylbdjbyregklzdzhldszchznwczcllwjqjjjkdgjcolbbzppglghtgzcygezmycnqcycy"
                                  + "hbhgxkamtxyxnbskyzzgjzlqjdfcjxdygjqjjpmgwgjjjpkjsbgbmmcjssclpqpdxcdyykypcjddyygywchjrtgcnyql"
                                  + "dkljczzgzccjgdyksgpzmdlcphnjafyzdjcnmwescsglbtzcgmsdllyxqsxsbljsbbsgghfjlwpmzjnlyywdqshzxtyy"
                                  + "whmcyhywdbxbtlmswyyfsbjcbdxxlhjhfpsxzqhfzmqcztqcxzxrdkdjhnnyzqqfnqdmmgnydxmjgdhcdycbffallztd"
                                  + "ltfkmxqzdngeqdbdczjdxbzgsqqddjcmbkxffxmkdmcsychzcmljdjynhprsjmkmpcklgdbqtfzswtfgglyplljzhgjj"
                                  + "gypzltcsmcnbtjbhfkdhbyzgkpbbymtdlsxsbnpdkleycjnycdykzddhqgsdzsctarlltkzlgecllkjljjaqnbdggghf"
                                  + "jtzqjsecshalqfmmgjnlyjbbtmlycxdcjpldlpcqdhsycbzsckbzmsljflhrbjsnbrgjhxpdgdjybzgdlgcsezgxlblg"
                                  + "yxtwmabchecmwyjyzlljjshlgndjlslygkdzpzxjyyzlpcxszfgwyydlyhcljscmbjhblyjlycblydpdqysxktbytdkd"
                                  + "xjypcnrjmfdjgklccjbctbjddbblblcdqrppxjcglzcshltoljnmdddlngkaqakgjgyhheznmshrphqqjchgmfprxcjg"
                                  + "dychghlyrzqlcngjnzsqdkqjymszswlcfqjqxgbggxmdjwlmcrnfkkfsyyljbmqammmycctbshcptxxzzsmphfshmclm"
                                  + "ldjfyqxsdyjdjjzzhqpdszglssjbckbxyqzjsgpsxjzqznqtbdkwxjkhhgflbcsmdldgdzdblzkycqnncsybzbfglzzx"
                                  + "swmsccmqnjqsbdqsjtxxmbldxcclzshzcxrqjgjylxzfjphymzqqydfqjjlcznzjcdgzygcdxmzysctlkphtxhtlbjxj"
                                  + "lxscdqccbbqjfqzfsltjbtkqbsxjjljchczdbzjdczjccprnlqcgpfczlclcxzdmxmphgsgzgszzqjxlwtjpfsyaslcj"
                                  + "btckwcwmytcsjjljcqlwzmalbxyfbpnlschtgjwejjxxglljstgshjqlzfkcgnndszfdeqfhbsaqdgylbxmmygszldyd"
                                  + "jmjjrgbjgkgdhgkblgkbdmbylxwcxyttybkmrjjzxqjbhlmhmjjzmqasldcyxyqdlqcafywyxqhz";
                String _gbcode = GBCode.ToString();
                int pos = (Convert.ToInt16(_gbcode.Substring(0, 2)) - 56) * 94 + Convert.ToInt16(_gbcode.Substring(_gbcode.Length - 2, 2));
                return CodeData.Substring(pos - 1, 1);
            }
            return "";
        }
    }
}

aspx页:
 

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebApplication1._Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>无标题页</title>
</head>
<body>
    <form id="form1" runat="server">
     <div>
        输入汉字
        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
        <br />
        <br />
        拼音缩写
        <asp:Label ID="Label1" runat="server" Text=""></asp:Label><br />
        <br />
        <asp:Button ID="Button1" runat="server" Text="获得拼音缩写" OnClick="Button1_Click" />
    
    </div>
    </form>
</body>
</html>

aspx.cs文件

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

namespace WebApplication1
{
    public partial class _Default : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }
        protected void Button1_Click(object sender, EventArgs e)
        {
            if (TextBox1.Text != "")
            {
                GetAlphaFirst py = new GetAlphaFirst();
                Label1.Text = py.GetIndexCode(TextBox1.Text);
            }
            else
            {
                Label1.Text = "请输入要查询的文字";
            }
        }
    }
}