<!-- JS-&#unicode;编码转换 -->
<script type="text/javascript">
var toHTML = {
  on: function(str) {
    var a = [],
    i = 0;
    for (; i < str.length;) a[i] = str.charCodeAt(i++);
    return "&#" + a.join(";&#") + ";"
  },
  un: function(str) {
    return str.replace(/&#(x)?([^&]{1,5});?/g,
    function(a, b, c) {
      return String.fromCharCode(parseInt(c, b ? 16 : 10))
    })
  }
};
//alert(toHTML.on("\"请输\""));
//alert(toHTML.un("请输"));
</script>

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<!-- JS-unicode编码转换 -->
<script type="text/javascript">
var toUN = {
  on: function(str) {
    var a = [],
    i = 0;
    for (;i< str.length;){
      a[i] = ("00" + str.charCodeAt(i++).toString(16)).slice( - 4);
    }
    return "\\u" + a.join("\\u")
  },
  un: function(str) {
    return unescape(str.replace(/\\/g, "%"))
  }
};
//var b = 'Today is a lice day';
//alert(b.slice(-6,-2));
var a = '"';
alert(a.charCodeAt(0).toString(16).slice(-4));
//alert(toUN.on("\"请输\""));
//alert(toUN.un("\\u0022\\u8BF7\\u8F93\\u0022"));
</script>

?文章来源：http://hi.baidu.com/fegro/blog/item/b85b0e65361b9e36ab184cad.html