Alex1990

/**
 * Check if an event is supported.
 * Ref: http://perfectionkills.com/detecting-event-support-without-browser-sniffing/
 */
function isEventSupported(event) {
  var testEl = document.createElement('div');
  var isSupported;

  event = 'on' + event;
  isSupported = (event in testEl);

Alex1990

// Get the closest matched element of an element. (Include itself)
function closest(elem, className, context) {
  context = context || document;
  do {
    if (hasClass(elem, className)) return elem;
  } while ((elem = elem.parentNode) && elem !== context)
  
  return null;
}

Alex1990

/**
 * Get window/viewport width and height. The window.innerWidth value includes the scrollbar,
 * and document.documentElement.clientWidth/document.body.clientWidth doesn't include.
 * Compatibility: IE6+ and other modern browsers
 */
function winW() {
  return window.innerWidth || document.documentElement.clientWidth;
}

function winH() {

Alex1990

/**
 * A simple event delegation method.
 */

// closest method: https://gist.github.com/Alex1990/5547956babc593852c3a

function delegate(elem, type, selector, listener, capture) {
  listener._delegateWrapper = function(e) {
    if (e.delegateTarget = closest(e.target, selector, elem)) {
      listener.call(e.delegateTarget, e);

Alex1990

// Check if an element has the specified class.
function hasClass(el, cls) {
  return (' ' + el.className + ' ').indexOf(' ' + cls + ' ') > -1;
}

Alex1990

isIE = /MSIE|Trident/.test(navigator.userAgent);

// isIE = 'ActiveXObject' in window;

Alex1990

/**
 * IE 11 has discarded the "MSIE" feature string.
 */

isIE11 = /Trident.*rv:11\.0/.test(navigator.userAgent);

Alex1990

/**
 * Valid number primitive regular expression. The keyword "Infinity" is invalid.
 */
var rNumber = /^[+-]?(?:\d+\.?\d*|\.\d+)(?:[eE][+-]?\d+)?$/;

Alex1990

/**
 * Decimal number regular expression.
 *
 * Valid decimal strings: 
 *  ['1', '1.', '1.1', '.1', '+1', '+1.', '+1.1', '+.1', '-1', '-1.', '-1.1', '-.1']
 * Invalid decimal strings:
 *  ['', '.', '+.', '-.', '1.1.', '1..1', 'Infinity', '-Infinity']
 *
 * Ref:
 *  http://stackoverflow.com/questions/12117024/decimal-number-regular-expression

Alex1990

/**
 * A simple function to test performance.
 */
function benchmark() {
  var tests = Array.prototype.slice.call(arguments);
  var length = tests.length;
  var startTimes = Array(length);
  var result = Array(length);
  
  var times = typeof benchmark.times === 'number' ? benchmark.times/2 : 5000;