用VC实现汉字转拼音首字母

参考代码：http://blog.csdn.net/lixiaosan/archive/2006/05/26/756350.aspx
lixiaosan的代码用的是CString在Unicode下有问题，我这里稍作修改，用stl::string和stl::wstring替换CString

代码为两个文件：GenFirstPYLetter.h，GenFirstPYLetter.cpp

 /* -------------------------------------------------------------------------
 //  FileName    :   GenFirstPYLetter.h
 //  Creator     :   debehe
 //  Date        :   2009/9/28 17:40:24
 //  Brief       :   需要用MultiByte才能正确转换
 //                  Unicode转成MultiByte时不要用W2A
 //
 //  $Id: $
 // -----------------------------------------------------------------------*/
 // How to use:
 //
 // std::wstring strA = L"WPS电子表格";
 // std::wstring strOutput;
 // BOOL bRet = GenFirstPYLetter(strA, strOutput);
 //
 // 结果应该是:
 // strOutput == L"WPSDZBG";
 // bRet == TRUE; // 以字母开头

 // -------------------------------------------------------------------------

 #ifndef __GETFIRSTLETTER_H__
 #define __GETFIRSTLETTER_H__

 #include <Windows.h>
 #include <string>
 // -------------------------------------------------------------------------

 /*
 @ Function  : GenFirstPYLetter
 @ brief     : 转换汉字为拼音首字母
 @ parameter : [in]strName
 @ parameter : [out]strResult
 @ return    : 是否以字母开头
 @ remark    :
 @ Date      : 2009/9/28 20:37:19 linyehui
 @*/
 BOOL GenFirstPYLetter(std::string strName, std::string&strResult );

 BOOL GenFirstPYLetter(std::wstring strName, std::wstring&strResult);


 // -------------------------------------------------------------------------
 // $Log: $

 #endif /* __GETFIRSTLETTER_H__ */

 /* -------------------------------------------------------------------------
 //  FileName    :   GenFirstPYLetter.cpp
 //  Creator     :   debehe
 //  Date        :   2009/9/28 17:40:31
 //  Brief       :   需要用MultiByte才能正确转换
 //                  Unicode转成MultiByte时不要用W2A
 //
 //  $Id: $
 // -----------------------------------------------------------------------*/

 #include "stdafx.h"
 #include "GenFirstPYLetter.h"
 #include <Windows.h>

 // -------------------------------------------------------------------------

 /********************************************************************************************
 /* Syntax
 /*        void FirstLetter(int nCode, CString& strLetter)
 /* Remarks:
 /*        Get the first letter of pinyin according to specified Chinese character code.
 /* Parameters:
 /*        nCode         - the code of the chinese character.
 /*        strLetter      - a CString object that is to receive the string of the first letter.
 /* Return Values:
 /*        None.
 /* Author:
 /*        lixiaosan
 /* Create Date:
 /*        05-26-2006
 /********************************************************************************************/
 void FirstLetter(int nCode, std::string& strLetter)
 {
     if(nCode >= 1601 && nCode < 1637) strLetter = "A";
     if(nCode >= 1637 && nCode < 1833) strLetter = "B";
     if(nCode >= 1833 && nCode < 2078) strLetter = "C";
     if(nCode >= 2078 && nCode < 2274) strLetter = "D";
     if(nCode >= 2274 && nCode < 2302) strLetter = "E";
     if(nCode >= 2302 && nCode < 2433) strLetter = "F";
     if(nCode >= 2433 && nCode < 2594) strLetter = "G";
     if(nCode >= 2594 && nCode < 2787) strLetter = "H";
     if(nCode >= 2787 && nCode < 3106) strLetter = "J";
     if(nCode >= 3106 && nCode < 3212) strLetter = "K";
     if(nCode >= 3212 && nCode < 3472) strLetter = "L";
     if(nCode >= 3472 && nCode < 3635) strLetter = "M";
     if(nCode >= 3635 && nCode < 3722) strLetter = "N";
     if(nCode >= 3722 && nCode < 3730) strLetter = "O";
     if(nCode >= 3730 && nCode < 3858) strLetter = "P";
     if(nCode >= 3858 && nCode < 4027) strLetter = "Q";
     if(nCode >= 4027 && nCode < 4086) strLetter = "R";
     if(nCode >= 4086 && nCode < 4390) strLetter = "S";
     if(nCode >= 4390 && nCode < 4558) strLetter = "T";
     if(nCode >= 4558 && nCode < 4684) strLetter = "W";
     if(nCode >= 4684 && nCode < 4925) strLetter = "X";
     if(nCode >= 4925 && nCode < 5249) strLetter = "Y";
     if(nCode >= 5249 && nCode < 5590) strLetter = "Z";
 }

 BOOL GenFirstPYLetter(std::string strName, std::string&strResult )
 {
     BOOL bStartByLetter = FALSE;

     unsigned char ucHigh, ucLow;
     int  nCode;
     std::string strRet;

     strResult.clear();

     if (strName.empty())
         return FALSE;

     if ((unsigned char)strName[0] < 0x80 )
         bStartByLetter = TRUE;

     for (size_t i=0; i < strName.size(); i++)
     {
         if ( (unsigned char)strName[i] < 0x80 )
         {
             strResult += strName[i];
             continue;
         }

         ucHigh = (unsigned char)strName[i];
         ucLow  = (unsigned char)strName[i+1];
         if ( ucHigh < 0xa1 || ucLow < 0xa1)
             continue;
         else
             // Treat code by section-position as an int type parameter,
             // so make following change to nCode.
             nCode = (ucHigh - 0xa0) * 100 + ucLow - 0xa0;

         FirstLetter(nCode, strRet);
         strResult += strRet;
         i++;
     }

     return bStartByLetter;
 }

 BOOL GenFirstPYLetter(std::wstring strName, std::wstring&strResult)
 {
     std::string strSource;
     std::string strOutput;

     // Unicode转换成MultiByte
     DWORD dwNum = WideCharToMultiByte(CP_OEMCP,NULL,strName.c_str(),-1,NULL,0,NULL,FALSE);
     char *psText;
     psText = new char[dwNum];
     if(!psText)
     {
         delete []psText;
         return FALSE;
     }
     else
     {
         WideCharToMultiByte (CP_OEMCP,NULL,strName.c_str(),-1,psText,dwNum,NULL,FALSE);
         strSource = psText;
         delete []psText;
     }

     // 转调
     BOOL bRet = GenFirstPYLetter(strSource, strOutput);

     // MultiByte转换成Unicode
     dwNum = MultiByteToWideChar (CP_ACP, 0, strOutput.c_str(), -1, NULL, 0);

     wchar_t *pwText;
     pwText = new wchar_t[dwNum];
     if(!pwText)
     {
         delete []pwText;
         return FALSE;
     }
     else
     {
         MultiByteToWideChar (CP_ACP, 0, strOutput.c_str(), -1, pwText, dwNum);
         strResult = pwText;
         delete [] pwText;
     }

     return bRet;
 }

 // -------------------------------------------------------------------------
 // $Log: $