https://www.mysprintt.eu/misc/jquery.once_v-1.2.js

1/**
2 * jQuery Once Plugin v1.2
3 * http://plugins.jquery.com/project/once
4 *
5 * Dual licensed under the MIT and GPL licenses:
6 *   http://www.opensource.org/licenses/mit-license.php
7 *   http://www.gnu.org/licenses/gpl.html
8 */
9
10(function ($) {
11  var cache = {}, uuid = 0;
12
13  /**
14   * Filters elements by whether they have not yet been processed.
15   *
16   * @param id
17   *   (Optional) If this is a string, then it will be used as the CSS class
18   *   name that is applied to the elements for determining whether it has
19   *   already been processed. The elements will get a class in the form of
20   *   "id-processed".
21   *
22   *   If the id parameter is a function, it will be passed off to the fn
23   *   parameter and the id will become a unique identifier, represented as a
24   *   number.
25   *
26   *   When the id is neither a string or a function, it becomes a unique
27   *   identifier, depicted as a number. The element's class will then be
28   *   represented in the form of "jquery-once-#-processed".
29   *
30   *   Take note that the id must be valid for usage as an element's class name.
31   * @param fn
32   *   (Optional) If given, this function will be called for each element that
33   *   has not yet been processed. The function's return value follows the same
34   *   logic as $.each(). Returning true will continue to the next matched
35   *   element in the set, while returning false will entirely break the
36   *   iteration.
37   */
38  $.fn.once = function (id, fn) {
39    if (typeof id != 'string') {
40      // Generate a numeric ID if the id passed can't be used as a CSS class.
41      if (!(id in cache)) {
42        cache[id] = ++uuid;
43      }
44      // When the fn parameter is not passed, we interpret it from the id.
45      if (!fn) {
46        fn = id;
47      }
48      id = 'jquery-once-' + cache[id];
49    }
50    // Remove elements from the set that have already been processed.
51    var name = id + '-processed';
52    var elements = this.not('.' + name).addClass(name);
53
54    return $.isFunction(fn) ? elements.each(fn) : elements;
55  };
56
57  /**
58   * Filters elements that have been processed once already.
59   *
60   * @param id
61   *   A required string representing the name of the class which should be used
62   *   when filtering the elements. This only filters elements that have already
63   *   been processed by the once function. The id should be the same id that
64   *   was originally passed to the once() function.
65   * @param fn
66   *   (Optional) If given, this function will be called for each element that
67   *   has not yet been processed. The function's return value follows the same
68   *   logic as $.each(). Returning true will continue to the next matched
69   *   element in the set, while returning false will entirely break the
70   *   iteration.
71   */
72  $.fn.removeOnce = function (id, fn) {
73    var name = id + '-processed';
74    var elements = this.filter('.' + name).removeClass(name);
75
76    return $.isFunction(fn) ? elements.each(fn) : elements;
77  };
78})(jQuery);