跨平台Unicode与UTF8互转代码

参考来源:http://blog.csdn.net/flying8127/article/details/1598521

在原来原基础上,将代码整理,并加强安全性. 并按照WindowsAPI设计, 添加输出缓冲长度探测功能

当OutUTFString为NULL时, 可以进行输出的UTF8字符串长度探测

   1:  uint32 UniCharToUTF8(wchar_t UniChar, char *OutUTFString)

   2:      {

   3:   

   4:          uint32 UTF8CharLength = 0;

   5:   

   6:          if (UniChar < 0x80)

   7:          {  

   8:              if ( OutUTFString )

   9:                  OutUTFString[UTF8CharLength++] = (char)UniChar;

  10:              else

  11:                  UTF8CharLength++;

  12:          }

  13:          else if(UniChar < 0x800)

  14:          {

  15:              if ( OutUTFString )

  16:              {

  17:                  OutUTFString[UTF8CharLength++] = 0xc0 | ( UniChar >> 6 );

  18:                  OutUTFString[UTF8CharLength++] = 0x80 | ( UniChar & 0x3f );

  19:              }

  20:              else

  21:              {

  22:                  UTF8CharLength += 2;

  23:              }

  24:          }

  25:          else if(UniChar < 0x10000 )

  26:          {

  27:              if ( OutUTFString )

  28:              {

  29:                  OutUTFString[UTF8CharLength++] = 0xe0 | ( UniChar >> 12 );

  30:                  OutUTFString[UTF8CharLength++] = 0x80 | ( (UniChar >> 6) & 0x3f );

  31:                  OutUTFString[UTF8CharLength++] = 0x80 | ( UniChar & 0x3f );

  32:              }

  33:              else

  34:              {

  35:                  UTF8CharLength += 3;

  36:              }

  37:          }

  38:          else if( UniChar < 0x200000 ) 

  39:          {

  40:              if ( OutUTFString )

  41:              {

  42:                  OutUTFString[UTF8CharLength++] = 0xf0 | ( (int)UniChar >> 18 );

  43:                  OutUTFString[UTF8CharLength++] = 0x80 | ( (UniChar >> 12) & 0x3f );

  44:                  OutUTFString[UTF8CharLength++] = 0x80 | ( (UniChar >> 6) & 0x3f );

  45:                  OutUTFString[UTF8CharLength++] = 0x80 | ( UniChar & 0x3f );

  46:              }

  47:              else

  48:              {

  49:                  UTF8CharLength += 4;

  50:              }

  51:   

  52:          }

  53:   

  54:          return UTF8CharLength;

  55:      }

当OutUnicodeString为NULL时, 可以进行输出的Unicode字符串长度探测

   1:  uint32 UTF8StrToUnicode( const char* UTF8String, uint32 UTF8StringLength, wchar_t* OutUnicodeString, uint32 UnicodeStringBufferSize )

   2:      {

   3:          uint32 UTF8Index = 0;

   4:          uint32 UniIndex = 0;

   5:   

   6:          while ( UTF8Index < UTF8StringLength )

   7:          {

   8:              unsigned char UTF8Char = UTF8String[UTF8Index];

   9:   

  10:              if ( UnicodeStringBufferSize != 0 && UniIndex >= UnicodeStringBufferSize )

  11:                  break;

  12:   

  13:              if ((UTF8Char & 0x80) == 0) 

  14:              {

  15:                  const uint32 cUTF8CharRequire = 1;

  16:   

  17:                  // UTF8字码不足

  18:                  if ( UTF8Index + cUTF8CharRequire > UTF8StringLength )

  19:                      break;

  20:   

  21:                  if ( OutUnicodeString )

  22:                  {

  23:                      wchar_t& WideChar = OutUnicodeString[UniIndex]; 

  24:   

  25:                      WideChar = UTF8Char;

  26:                  }

  27:   

  28:                  UTF8Index++;

  29:                  

  30:              } 

  31:              else if((UTF8Char & 0xE0) == 0xC0)  ///< 110x-xxxx 10xx-xxxx

  32:              {

  33:                  const uint32 cUTF8CharRequire = 2;

  34:   

  35:                  // UTF8字码不足

  36:                  if ( UTF8Index + cUTF8CharRequire > UTF8StringLength )

  37:                      break;

  38:   

  39:                  if ( OutUnicodeString )

  40:                  {

  41:                      wchar_t& WideChar = OutUnicodeString[UniIndex]; 

  42:                      WideChar  = (UTF8String[UTF8Index + 0] & 0x3F) << 6;

  43:                      WideChar |= (UTF8String[UTF8Index + 1] & 0x3F);

  44:                  }

  45:                  

  46:                  UTF8Index += cUTF8CharRequire;

  47:              }

  48:              else if((UTF8Char & 0xF0) == 0xE0)  ///< 1110-xxxx 10xx-xxxx 10xx-xxxx

  49:              {

  50:                  const uint32 cUTF8CharRequire = 3;

  51:   

  52:                  // UTF8字码不足

  53:                  if ( UTF8Index + cUTF8CharRequire > UTF8StringLength )

  54:                      break;

  55:   

  56:                  if ( OutUnicodeString )

  57:                  {

  58:                      wchar_t& WideChar = OutUnicodeString[UniIndex]; 

  59:   

  60:                      WideChar  = (UTF8String[UTF8Index + 0] & 0x1F) << 12;

  61:                      WideChar |= (UTF8String[UTF8Index + 1] & 0x3F) << 6;

  62:                      WideChar |= (UTF8String[UTF8Index + 2] & 0x3F);

  63:                  }

  64:                  

  65:   

  66:                  UTF8Index += cUTF8CharRequire;

  67:              } 

  68:              else if((UTF8Char & 0xF8) == 0xF0)  ///< 1111-0xxx 10xx-xxxx 10xx-xxxx 10xx-xxxx 

  69:              {

  70:                  const uint32 cUTF8CharRequire = 4;

  71:   

  72:                  // UTF8字码不足

  73:                  if ( UTF8Index + cUTF8CharRequire > UTF8StringLength )

  74:                      break;

  75:   

  76:                  if ( OutUnicodeString )

  77:                  {

  78:                      wchar_t& WideChar = OutUnicodeString[UniIndex]; 

  79:   

  80:                      WideChar  = (UTF8String[UTF8Index + 0] & 0x0F) << 18;

  81:                      WideChar  = (UTF8String[UTF8Index + 1] & 0x3F) << 12;

  82:                      WideChar |= (UTF8String[UTF8Index + 2] & 0x3F) << 6;

  83:                      WideChar |= (UTF8String[UTF8Index + 3] & 0x3F);

  84:                  }

  85:   

  86:                  UTF8Index += cUTF8CharRequire;

  87:              } 

  88:              else ///< 1111-10xx 10xx-xxxx 10xx-xxxx 10xx-xxxx 10xx-xxxx 

  89:              {

  90:                  const uint32 cUTF8CharRequire = 5;

  91:   

  92:                  // UTF8字码不足

  93:                  if ( UTF8Index + cUTF8CharRequire > UTF8StringLength )

  94:                      break;

  95:   

  96:                  if ( OutUnicodeString )

  97:                  {

  98:                      wchar_t& WideChar = OutUnicodeString[UniIndex]; 

  99:   

 100:                      WideChar  = (UTF8String[UTF8Index + 0] & 0x07) << 24;

 101:                      WideChar  = (UTF8String[UTF8Index + 1] & 0x3F) << 18;

 102:                      WideChar  = (UTF8String[UTF8Index + 2] & 0x3F) << 12;

 103:                      WideChar |= (UTF8String[UTF8Index + 3] & 0x3F) << 6;

 104:                      WideChar |= (UTF8String[UTF8Index + 4] & 0x3F);

 105:                  }

 106:   

 107:                  UTF8Index += cUTF8CharRequire;

 108:              }

 109:   

 110:   

 111:              UniIndex++;

 112:          }

 113:   

 114:          return UniIndex;

 115:      }

疗效: 用了此代码啊, 再也不用被iconv折磨了