JS中文字符串和UTF-8编码字符串相互转换

JS中文字符串和UTF-8编码字符串相互转换

1.中文字符串转化为UTF-8编码，如“<汉字>”的UTF-8编码为“%3C%E6%B1%89%E5%AD%97%3E”
2.UTF-8编码字符串“%E6%B1%89%E5%AD%97”的中文为“<汉字>”

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)));

           }
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 "";
} 

var test = EncodeUtf8("中国");
alert("中国-----"+test);
</script>
    <script language="JavaScript">
//字符串替换函数,全部替换
function strReplaceAll(str,oldStr,newStr){
var regS = new RegExp(oldStr,"gi");
    newStr = str.replace(regS,newStr);
return newStr;   
}
</script>

<script> 
//UTF-8编码的汉字转换为字符，特殊字符未处理，
function chineseFromUtf8Url(strUtf8) 
{ 
var   bstr   =   ""; 
var   nOffset   =   0; // processing point on strUtf8 

if(   strUtf8   ==   ""   ) 
return   ""; 

strUtf8   =   strUtf8.toLowerCase(); 
nOffset   =   strUtf8.indexOf("%e"); 
if(   nOffset   ==   -1   ) 
return   strUtf8; 

while(   nOffset   !=   -1   ) 
{ 
      bstr   +=   strUtf8.substr(0,   nOffset); 
      strUtf8   =   strUtf8.substr(nOffset,   strUtf8.length   -   nOffset); 
if(   strUtf8   ==   ""   ||   strUtf8.length   <   9   )       // bad string 
return   bstr; 

      bstr   +=   utf8CodeToChineseChar(strUtf8.substr(0,   9)); 
      strUtf8   =   strUtf8.substr(9,   strUtf8.length   -   9); 
      nOffset   =   strUtf8.indexOf("%e"); 
} 

return   bstr   +   strUtf8; 
} 

function unicodeFromUtf8(strUtf8) 
{ 
var   bstr   =   ""; 
var   nTotalChars   =   strUtf8.length; // total chars to be processed. 
var   nOffset   =   0; // processing point on strUtf8 
var   nRemainingBytes   =   nTotalChars; // how many bytes left to be converted 
var   nOutputPosition   =   0; 
var   iCode,   iCode1,   iCode2; // the value of the unicode. 

while   (nOffset   <   nTotalChars) 
{ 
iCode   =   strUtf8.charCodeAt(nOffset); 
if   ((iCode   &   0x80)   ==   0) // 1 byte. 
{ 
if   (   nRemainingBytes   <   1   ) // not enough data 
break; 

bstr   +=   String.fromCharCode(iCode   &   0x7F); 
nOffset   ++; 
nRemainingBytes   -=   1; 
} 
else   if   ((iCode   &   0xE0)   ==   0xC0) // 2 bytes 
{ 
iCode1   =     strUtf8.charCodeAt(nOffset   +   1); 
if   (   nRemainingBytes   <   2   || // not enough data 
    (iCode1   &   0xC0)   !=   0x80   ) // invalid pattern 
{ 
break; 
} 

bstr   +=   String.fromCharCode(((iCode   &   0x3F)   <<   6)   |   (   iCode1   &   0x3F)); 
nOffset   +=   2; 
nRemainingBytes   -=   2; 
} 
else   if   ((iCode   &   0xF0)   ==   0xE0) // 3 bytes 
{ 
iCode1   =     strUtf8.charCodeAt(nOffset   +   1); 
iCode2   =     strUtf8.charCodeAt(nOffset   +   2); 
if   (   nRemainingBytes   <   3   || // not enough data 
    (iCode1   &   0xC0)   !=   0x80   || // invalid pattern 
    (iCode2   &   0xC0)   !=   0x80   ) 
{ 
break; 
} 

bstr   +=   String.fromCharCode(((iCode   &   0x0F)   <<   12)   |    
((iCode1   &   0x3F)   <<     6)   | 
(iCode2   &   0x3F)); 
nOffset   +=   3; 
nRemainingBytes   -=   3; 
} 
else // 4 or more bytes -- unsupported 
break; 
} 

if   (nRemainingBytes   !=   0) 
{ 
// bad UTF8 string. 
return   ""; 
} 


return   bstr; 

} 

function utf8CodeToChineseChar(strUtf8) 
{ 
var   iCode,   iCode1,   iCode2; 
      iCode   =   parseInt("0x"   +   strUtf8.substr(1,   2)); 
      iCode1   =   parseInt("0x"   +   strUtf8.substr(4,   2)); 
      iCode2   =   parseInt("0x"   +   strUtf8.substr(7,   2)); 

return   String.fromCharCode(((iCode   &   0x0F)   <<   12)   |    
((iCode1   &   0x3F)   <<     6)   | 
(iCode2   &   0x3F)); 
} 

var test ="%3CHTML%3E %3CHEAD%3E %3CCENTER%3E %3CH1%3EEncountered an NDS error while updating the new password. %3CP%3EPlease contact the system administrator. %3C/H1%3E %3C/CENTER%3E %3C/HEAD%3E %3C/HTML%3E";

//替换掉中文字符串中的括号“<>”
    test = strReplaceAll(test,"%3C","<");
    test = strReplaceAll(test,"%3E",">");


alert(chineseFromUtf8Url("%3CHTML%3E %3CHEAD%3E %3CCENTER%3E %3CH1%3EEncountered an NDS error while updating the new password. %3CP%3EPlease contact the system administrator. %3C/H1%3E %3C/CENTER%3E %3C/HEAD%3E %3C/HTML%3E------"+test)) 

</script>


<script language="javascript">
//替换所有字符
function replace(str,a,b)
 {
var i;
var s2 = str;

while(s2.indexOf(a)>0)
     {
     i = s2.indexOf(a);
     s2 = s2.substring(0, i) + b
     + s2.substring(i + 2, s2.length);
     }
return s2;
    }
</script>