SYNTAX_ERR: DOM Exception 12 - Hmmm

Isaac Lewis picture Isaac Lewis · Sep 6, 2011 · Viewed 56.6k times · Source

I have been working on a small slideshow / public display for a client that uses HTML5 Rock's Slideshow code. I have run into a DOM Exception 12 - a syntax error that is supposedly related to CSS selectors - while monkeying around with it... but I can't trace it back to any changes I made in the code. I am thinking it might be something that was uncovered as I added features.

I have traced it down to this object (live version here):

var SlideShow = function(slides) {
    this._slides = (slides || []).map(function(el, idx) {
      return new Slide(el, idx);
    });
    var h = window.location.hash;
    try {
      this.current = h;
    } catch (e) { /* squeltch */ }
    this.current = (!this.current) ? "landing-slide" : this.current.replace('#', '');
    if (!query('#' + this.current)) {
      // if this happens is very likely that someone is coming from
      // a link with the old permalink format, i.e. #slide24
      alert('The format of the permalinks have recently changed. If you are coming ' +
             'here from an old external link it\'s very likely you will land to the wrong slide');
      this.current = "landing-slide";
    }
    var _t = this;
    doc.addEventListener('keydown',
        function(e) { _t.handleKeys(e); }, false);
    doc.addEventListener('touchstart',
        function(e) { _t.handleTouchStart(e); }, false);
    doc.addEventListener('touchend',
        function(e) { _t.handleTouchEnd(e); }, false);
    window.addEventListener('popstate',
        function(e) { if (e.state) { _t.go(e.state, true); } }, false);
};

Instantiation of SlideShow() (line 521 in main.js):

var slideshow = new SlideShow(queryAll('.slide'));

Calling queryAll('.slide') returns an array of all the slides with an class of .slide. However, when passing queryAll('.slide') as a parameter for instantiating SlideShow(), it returns a DOM Exception 12 error.

Has anybody seen this before?

Answer

Dr.Molle picture Dr.Molle · Sep 6, 2011

You are using illegal id-attributes(illegal before HTML5) inside the document, e.g. 2-slide . Fix them.

To explain: to solve the known misbehaviour of element.querySelectorAll() the selector .slide will be internally rewritten(by using the id of the element). This will result in something like that:

#2-slide .moreselectors

...and forces the error, because an ID may not start with a Number.

See the fiddle: http://jsfiddle.net/doktormolle/FGWhk/