Basic Knockout.js 'hidden' binding. Uses jQuery.

ko-jquery-hidden.js

/**
 * Knockout Extension: Hidden
 *
 * The inverse of the `visible` binding: hides the element when the observable
 * is true, shows it when the observable is false.
 *
 * @requires Knockout.js
 * @requires jQuery
 * @author Jon Stout (www.jonstout.net)
 */

'use strict';

(function(ko, $) {

  if (typeof ko.bindingHandlers.hidden === 'undefined') {

    ko.bindingHandlers.hidden = {
      update: function(element, valueAccessor) {
        var isHidden = ko.unwrap(valueAccessor());
        if (isHidden) {
          $(element).hide();
        } else {
          $(element).show();
        }
      }
    };

  }

})(ko, jQuery);