UTF-8、Unicode、Gb2312编码之间的转换类

class CChineseCode
{
   public:
// 把UTF-8转换成Unicode
       static void UTF_8ToUnicode(wchar_t* pOut,char *pText);
//Unicode 转换成UTF-8
       static void UnicodeToUTF_8(char* pOut,wchar_t* pText);
// 把Unicode 转换成 GB2312
       static void UnicodeToGB2312(char* pOut,wchar_t uData);
// GB2312 转换成　Unicode
       static void Gb2312ToUnicode(wchar_t* pOut,char *gbBuffer);
//GB2312 转为 UTF-8
       static void GB2312ToUTF_8(string& pOut,char *pText, int pLen);
//UTF-8 转为 GB2312
       static void UTF_8ToGB2312(string &pOut, char *pText, int pLen);
};

类实现

void CChineseCode::UTF_8ToUnicode(wchar_t* pOut,char *pText)
{
    char* uchar = (char *)pOut;

    uchar[1] = ((pText[0] & 0x0F) << 4) + ((pText[1] >> 2) & 0x0F);
    uchar[0] = ((pText[1] & 0x03) << 6) + (pText[2] & 0x3F);

    return;
}

void CChineseCode::UnicodeToUTF_8(char* pOut,wchar_t* pText)
{
    // 注意 WCHAR高低字的顺序,低字节在前，高字节在后
    char* pchar = (char *)pText;

    pOut[0] = (0xE0 | ((pchar[1] & 0xF0) >> 4));
    pOut[1] = (0x80 | ((pchar[1] & 0x0F) << 2)) + ((pchar[0] & 0xC0) >> 6);
    pOut[2] = (0x80 | (pchar[0] & 0x3F));

    return;
}

void CChineseCode::UnicodeToGB2312(char* pOut,wchar_t uData)
{
    WideCharToMultiByte(CP_ACP,NULL,&uData,1,pOut,sizeof(wchar_t),NULL,NULL);
    return;
}     

void CChineseCode::Gb2312ToUnicode(wchar_t* pOut,char *gbBuffer)
{
    ::MultiByteToWideChar(CP_ACP,MB_PRECOMPOSED,gbBuffer,2,pOut,1);
    return ;
}

void CChineseCode::GB2312ToUTF_8(string& pOut,char *pText, int pLen)
{
    char buf[4];
    int nLength = pLen* 3;
    char* rst = new char[nLength];

    memset(buf,0,4);
    memset(rst,0,nLength);

    int i = 0;
    int j = 0;      
    while(i < pLen)
    {
            //如果是英文直接复制就可以
            if( *(pText + i) >= 0)
            {
                    rst[j++] = pText[i++];
            }
            else
            {
                    wchar_t pbuffer;
                    Gb2312ToUnicode(&pbuffer,pText+i);

                    UnicodeToUTF_8(buf,&pbuffer);

                    unsigned short int tmp = 0;
                    tmp = rst[j] = buf[0];
                    tmp = rst[j+1] = buf[1];
                    tmp = rst[j+2] = buf[2];    

                    j += 3;
                    i += 2;
            }
    }
    rst[j] = '\0';

    //返回结果
    pOut = rst;             
    delete []rst;   

    return;
}

void CChineseCode::UTF_8ToGB2312(string &pOut, char *pText, int pLen)
{
    char * newBuf = new char[pLen];
    char Ctemp[4];
    memset(Ctemp,0,4);

    int i =0;
    int j = 0;

    while(i < pLen)
    {
        if(pText > 0)
        {
                newBuf[j++] = pText[i++];                       
        }
        else                 
        {
                WCHAR Wtemp;
                UTF_8ToUnicode(&Wtemp,pText + i);

                UnicodeToGB2312(Ctemp,Wtemp);

                newBuf[j] = Ctemp[0];
                newBuf[j + 1] = Ctemp[1];

                i += 3;    
                j += 2;   
        }
    }
    newBuf[j] = '\0';

    pOut = newBuf;
    delete []newBuf;

    return;
}