HTML encoding

encode.js

// use jQuery

function htmlEncode(value){
  //create a in-memory div, set it's inner text(which jQuery automatically encodes)
  //then grab the encoded contents back out.  The div never exists on the page.
  return $('<div/>').text(value).html();
}

function htmlDecode(value){
  return $('<div/>').html(value).text();
}

// hue javascript
function htmlEncode( html ) {
    return document.createElement( 'a' ).appendChild( 
        document.createTextNode( html ) ).parentNode.innerHTML;
};

function htmlDecode( html ) {
    var a = document.createElement( 'a' ); a.innerHTML = html;
    return a.textContent;
};

document.getElementById( 'text' ).value = htmlEncode( document.getElementById( 'hidden' ).value );

//sanity check
var html = '<div>   &amp; hello</div>';
document.getElementById( 'same' ).textContent = 
      'html === htmlDecode( htmlEncode( html ) ): ' 
    + ( html === htmlDecode( htmlEncode( html ) ) );

test.html

<!-- for hue -->
<input id="hidden" type="hidden" value="chalk    &amp; cheese" />
<input id="text" value="" />
<div id="same"></div>