Javascript UTF-8 encode/decode

var Utf8 = {
 // public method for url encoding
 encode : function (string) {
 string = string.replace(/\r\n/g,"\n");
 var utftext = "";
 
 for (var n = 0; n < string.length; n++) {
  var c = string.charCodeAt(n);
  if (c < 128) {
   utftext += String.fromCharCode(c);
  }
  else if((c > 127) && (c < 2048)) {
   utftext += String.fromCharCode((c >> 6) | 192);
   utftext += String.fromCharCode((c & 63) | 128);
  }
  else {
   utftext += String.fromCharCode((c >> 12) | 224);
   utftext += String.fromCharCode(((c >> 6) & 63) | 128);
   utftext += String.fromCharCode((c & 63) | 128);
  }
 }
 return utftext;
},

 // public method for url decoding
 decode : function (utftext) {
  var string = "";
  var i = 0;
  var c = c1 = c2 = 0;
  
  while ( i < utftext.length ) {
   c = utftext.charCodeAt(i);
   if (c < 128) {
    string += String.fromCharCode(c);
    i++;
   }
   else if((c > 191) && (c < 224)) {
    c2 = utftext.charCodeAt(i+1);
    string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
    i += 2;
   }
   else {
    c2 = utftext.charCodeAt(i+1);
    c3 = utftext.charCodeAt(i+2);
    string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
    i += 3;
   }
  }
  return string;
 }
}

demo:
alert(Utf8.encode('São Paulo'));