js 编码转换 gb2312 和 utf8 互转的2种方法

function gb2utf8(data){ 
      var glbEncode = []; 
      gb2utf8_data = data; 
      execScript("gb2utf8_data = MidB(gb2utf8_data, 1)", "VBScript"); 
      var t=escape(gb2utf8_data).replace(/%u/g,"").replace(/(.{2})(.{2})/g,"%$2%$1").replace(/%([A-Z].)%(.{2})/g,"@$1$2"); 
      t=t.split("@"); 
      var i=0,j=t.length,k; 
      while(++i<j) { 
         k=t[i].substring(0,4); 
         if(!glbEncode[k])  
         { 
            gb2utf8_char = eval("0x"+k); 
            execScript("gb2utf8_char = Chr(gb2utf8_char)", "VBScript"); 
            glbEncode[k]=escape(gb2utf8_char).substring(1,6); 
         } 
         t[i]=glbEncode[k]+t[i].substring(4); 
      } 
      gb2utf8_data = gb2utf8_char = null; 
      return unescape(t.join("%")); 
 }

<script language="JavaScript">
 <!--
 function utf8(wide) {
 var c, s;
 var enc = "";
 var i = 0;
 while(i<wide.length) {
 c= wide.charCodeAt(i++);
 // handle UTF-16 surrogates
 if (c>=0xDC00 && c<0xE000) continue;
 if (c>=0xD800 && c<0xDC00) {
 if (i>=wide.length) continue;
 s= wide.charCodeAt(i++);
 if (s<0xDC00 || c>=0xDE00) continue;
 c= ((c-0xD800)<<10)+(s-0xDC00)+0x10000;
 }
 // output value
 if (c<0x80) enc += String.fromCharCode(c);
 else if (c<0x800) enc += String.fromCharCode(0xC0+(c>>6),0x80+(c&0x3F));
 else if (c<0x10000) enc += String.fromCharCode(0xE0+(c>>12),0x80+(c>>6&0x3F),0x80+(c&0x3F));
 else enc += String.fromCharCode(0xF0+(c>>18),0x80+(c>>12&0x3F),0x80+(c>>6&0x3F),0x80+(c&0x3F));
 }
 return enc;
 }
 var hexchars = "0123456789ABCDEF";
 function toHex(n) {
 return hexchars.charAt(n>>4)+hexchars.charAt(n & 0xF);
 }
 var okURIchars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_-";
 function encodeURIComponentNew(s) {
 var s = utf8(s);
 var c;
 var enc = "";
 for (var i= 0; i<s.length; i++) {
 if (okURIchars.indexOf(s.charAt(i))==-1)
 enc += "%"+toHex(s.charCodeAt(i));
 else
 enc += s.charAt(i);
 }
 return enc;
 }
 alert(encodeURIComponentNew("中文"))
 alert(decodeURIComponent(encodeURIComponentNew("中文")))
 // -->
 </script>

String dwp = new String(request.getParameter("dwp").getBytes("ISO-8859-1"),"gbk") ; 
String dwc = new String(request.getParameter("dwc").getBytes("ISO-8859-1"),"gbk") ;