javascript gb2312ToUtf8编码

<script type="text/javascript">
function EncodeUtf8(s1)
  {
      var s = escape(s1);
      var sa = s.split("%");
      var retV ="";
      if(sa[0] != "")
      {
         retV = sa[0];
      }
      for(var i = 1; i < sa.length; i ++)
      {
           if(sa[i].substring(0,1) == "u")
           {
               retV += Hex2Utf8(Str2Hex(sa[i].substring(1,5))) + sa[i].substring(5,sa[i].length);
              
           }
           else retV += "%" + sa[i];
      }
     
      return retV;
  }
  function Str2Hex(s)
  {
      var c = "";
      var n;
      var ss = "0123456789ABCDEF";
      var digS = "";
      for(var i = 0; i < s.length; i ++)
      {
         c = s.charAt(i);
         n = ss.indexOf(c);
         digS += Dec2Dig(eval(n));
          
      }
      //return value;
      return digS;
  }
  function Dec2Dig(n1)
  {
      var s = "";
      var n2 = 0;
      for(var i = 0; i < 4; i++)
      {
         n2 = Math.pow(2,3 - i);
         if(n1 >= n2)
         {
            s += '1';
            n1 = n1 - n2;
          }
         else
          s += '0';
         
      }
      return s;
     
  }
  function Dig2Dec(s)
  {
      var retV = 0;
      if(s.length == 4)
      {
          for(var i = 0; i < 4; i ++)
          {
              retV += eval(s.charAt(i)) * Math.pow(2, 3 - i);
          }
          return retV;
      }
      return -1;
  }
  function Hex2Utf8(s)
  {
     var retS = "";
     var tempS = "";
     var ss = "";
     if(s.length == 16)
     {
         tempS = "1110" + s.substring(0, 4);
         tempS += "10" +  s.substring(4, 10);
         tempS += "10" + s.substring(10,16);
         var sss = "0123456789ABCDEF";
         for(var i = 0; i < 3; i ++)
         {
            retS += "%";
            ss = tempS.substring(i * 8, (eval(i)+1)*8);
           
           
           
            retS += sss.charAt(Dig2Dec(ss.substring(0,4)));
            retS += sss.charAt(Dig2Dec(ss.substring(4,8)));
         }
         return retS;
     }
     return "";
  }
document.write(EncodeUtf8("D 阿尔贝蒂尼"));
</script>