jQuery html() in Firefox (uses .innerHTML) ignores DOM changes

I'm really suprised I haven't run into this problem before, but it seems that calling jQueries .html() function on an element ignores changes in the DOM, i.e it returns the HTML in the original source. IE doesn't do this. jQueries .html() just uses the innerHTML property internally.

Is this meant to happen? I'm on Firefox 3.5.2. I have a sample below, where no matter what you change the textbox value to, the innerHTML of the "container" element only ever returns the value defined in the HTML markup. The sample isn't using jQuery just to make it simpler (the result is the same using jQuery).

Does anyone have a work around where I can get the html of a container in its current state, i.e. including any scripted changes to the DOM?

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
    <head>
        <script type="text/javascript">
            <!--
            function BodyLoad(){                
                document.getElementById("textbox").value = "initial UPDATE";
                DisplayTextBoxValue();
            }

            function DisplayTextBoxValue(){
                alert(document.getElementById("container").innerHTML);             
                return false;
            }
            //-->
        </script>
    </head>
    <body onload="BodyLoad();">
        <div id="container">
            <input type="text" id="textbox" value="initial" />
        </div>
        <input type="button" id="button" value="Test me" onclick="return DisplayTextBoxValue();" />
    </body>
</html>

Firefox doesn't update the value attribute of a DOM object based on user input, just its value property - pretty quick work around exists.

DOM:

function DisplayTextBoxValue(){
  var element = document.getElementById('textbox');
  // set the attribute on the DOM Element by hand - will update the innerHTML
  element.setAttribute('value', element.value);
  alert(document.getElementById("container").innerHTML);             
  return false;
}

jQuery plugin that makes .formhtml() automatically do this:

(function($) {
  var oldHTML = $.fn.html;

  $.fn.formhtml = function() {
    if (arguments.length) return oldHTML.apply(this,arguments);
    $("input,button", this).each(function() {
      this.setAttribute('value',this.value);
    });
    $("textarea", this).each(function() {
      // updated - thanks Raja & Dr. Fred!
      $(this).text(this.value);
    });
    $("input:radio,input:checkbox", this).each(function() {
      // im not really even sure you need to do this for "checked"
      // but what the heck, better safe than sorry
      if (this.checked) this.setAttribute('checked', 'checked');
      else this.removeAttribute('checked');
    });
    $("option", this).each(function() {
      // also not sure, but, better safe...
      if (this.selected) this.setAttribute('selected', 'selected');
      else this.removeAttribute('selected');
    });
    return oldHTML.apply(this);
  };

  //optional to override real .html() if you want
  // $.fn.html = $.fn.formhtml;
})(jQuery);

This is a known "issue" in Firefox. The specifications for innerHTML are not entirely clear, so different browser vendors implement it in a different way.

A discussion about this topic can be found here:

http://forums.mozillazine.org/viewtopic.php?t=317838#1744233

Thanks for your formhtml plugin. In order to use it with textarea, I had to update it :

$("textarea", this).each(function() { 
  $(this).text($(this).val()); 
});

I know your question relates to innerHTML, but if it were just the value of textbox inside container that you needed, then

$('#textbox').val()

will give the correct (updated) textbox value.

jQuery html() in Firefox (uses .innerHTML) ignores DOM changes

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