C++编码转换类

class CChineseCode
{
  public:
  static void UTF_8ToUnicode(wchar_t* pOut,char *pText); // 把UTF-8转换成Unicode
  static void UnicodeToUTF_8(char* pOut,wchar_t* pText); //Unicode 转换成UTF-8
  static void UnicodeToGB2312(char* pOut,wchar_t uData); // 把Unicode 转换成 GB2312  
  static void Gb2312ToUnicode(wchar_t* pOut,char *gbBuffer);// GB2312 转换成　Unicode

  static void GB2312ToUTF_8(string& pOut,char *pText, int pLen);//GB2312 转为 UTF-8
  static void UTF_8ToGB2312(string &pOut, char *pText, int pLen);//UTF-8 转为 GB2312
};

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能
  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] = ’’;

  //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] = ’’;
    
  pOut = newBuf;
  delete []newBuf;
    
  return;  
}