https://silkfact.jp/wp2/wp-content/plugins/xo-event-calendar/js/ajax.js?ver=3.2.10

1xo_event_calendar_month = function (e, month, event, categories, holidays, prev, next, start_of_week, months, navigation, title_format, is_locale, columns, base_month) {
2	var target = e.closest('.xo-event-calendar');
3	var id = target.getAttribute('id');
4	var request = new XMLHttpRequest();
5
6	target.setAttribute('disabled', 'disabled');
7	target.classList.add('xo-calendar-loading');
8
9	request.onreadystatechange = function () {
10		if (request.readyState === 4) {
11			if (200 <= request.status && request.status < 300) {
12				target.classList.remove('xo-calendar-loading');
13				target.getElementsByClassName('xo-months')[0].innerHTML =
14					request.response;
15			}
16		}
17	};
18
19	request.open('POST', xo_event_calendar_object.ajax_url, true);
20	request.setRequestHeader(
21		'content-type',
22		'application/x-www-form-urlencoded; charset=UTF-8'
23	);
24	request.send('action=' + xo_event_calendar_object.action +
25		'&id=' + id +
26		'&month=' + month +
27		'&event=' + event +
28		'&categories=' + categories +
29		'&holidays=' + holidays +
30		'&prev=' + prev +
31		'&next=' + next +
32		'&start_of_week=' + start_of_week +
33		'&months=' + months +
34		'&navigation=' + navigation +
35		'&title_format=' + title_format +
36		'&is_locale=' + is_locale +
37		'&columns=' + columns +
38		'&base_month=' + base_month
39	);
40
41	return false;
42};
43
44xo_simple_calendar_month = function (e, month, holidays, prev, next, start_of_week, months, navigation, title_format, is_locale, columns, caption_color, caption_bgcolor, base_month) {
45	var target = e.closest('.xo-simple-calendar');
46	var id = target.getAttribute('id');
47	var request = new XMLHttpRequest();
48
49	target.setAttribute('disabled', 'disabled');
50	target.classList.add('xo-calendar-loading');
51
52	request.onreadystatechange = function () {
53		if (request.readyState === 4) {
54			if (200 <= request.status && request.status < 300) {
55				target.classList.remove('xo-calendar-loading');
56				target.getElementsByClassName('calendars')[0].innerHTML = request.response;
57			}
58		}
59	};
60
61	request.open('POST', xo_simple_calendar_object.ajax_url, true);
62	request.setRequestHeader(
63		'content-type',
64		'application/x-www-form-urlencoded; charset=UTF-8'
65	);
66	request.send('action=' + xo_simple_calendar_object.action +
67		'&id=' + id +
68		'&month=' + month +
69		'&holidays=' + holidays +
70		'&prev=' + prev +
71		'&next=' + next +
72		'&start_of_week=' + start_of_week +
73		'&months=' + months +
74		'&navigation=' + navigation +
75		'&title_format=' + title_format +
76		'&is_locale=' + is_locale +
77		'&columns=' + columns +
78		'&caption_color=' + caption_color +
79		'&caption_bgcolor=' + caption_bgcolor +
80		'&base_month=' + base_month
81	);
82
83	return false;
84};