js手風琴無法正常工作IE9

Question

此頁面上的第一個問題。 我從http://codepen.io/chriswrightdesign/pen/cmanI此頁面上獲取了一個動畫的css / js手風琴，並且我剛剛在jsp Web應用程序中實現了它。

它在Chrome，Firefox和IE 11中運行良好。但是在IE 9中無法正常顯示。據我所知，我需要對一些js組件（classList，setAttribute和querySelectorAll）進行polyfill以獲得功能。在最后一個導航器中正常工作。

老實說，我對如何將這個js代碼進行代碼填充一無所知。 因此，如果有人可以幫助我，我將非常感激。

    //uses classList, setAttribute, and querySelectorAll
//if you want this to work in IE8/9 youll need to polyfill these
(function(){
    var d = document,
    accordionToggles = d.querySelectorAll('.js-accordionTrigger'),
    setAria,
    setAccordionAria,
    switchAccordion,
  touchSupported = ('ontouchstart' in window),
  pointerSupported = ('pointerdown' in window);

  skipClickDelay = function(e){
    e.preventDefault();
    e.target.click();
  }

        setAriaAttr = function(el, ariaType, newProperty){
        el.setAttribute(ariaType, newProperty);
    };
    setAccordionAria = function(el1, el2, expanded){
        switch(expanded) {
      case "true":
        setAriaAttr(el1, 'aria-expanded', 'true');
        setAriaAttr(el2, 'aria-hidden', 'false');
        break;
      case "false":
        setAriaAttr(el1, 'aria-expanded', 'false');
        setAriaAttr(el2, 'aria-hidden', 'true');
        break;
      default:
                break;
        }
    };
//function
switchAccordion = function(e) {
    e.preventDefault();
    var thisAnswer = e.target.parentNode.nextElementSibling;
    var thisQuestion = e.target;
    if(thisAnswer.classList.contains('is-collapsed')) {
        setAccordionAria(thisQuestion, thisAnswer, 'true');
    } else {
        setAccordionAria(thisQuestion, thisAnswer, 'false');
    }
    thisQuestion.classList.toggle('is-collapsed');
    thisQuestion.classList.toggle('is-expanded');
        thisAnswer.classList.toggle('is-collapsed');
        thisAnswer.classList.toggle('is-expanded');

    thisAnswer.classList.toggle('animateIn');
    };
    for (var i=0,len=accordionToggles.length; i<len; i++) {
        if(touchSupported) {
      accordionToggles[i].addEventListener('touchstart', skipClickDelay, false);
    }
    if(pointerSupported){
      accordionToggles[i].addEventListener('pointerdown', skipClickDelay, false);
    }
    accordionToggles[i].addEventListener('click', switchAccordion, false);
  }
})();

Answer 1

例如，IE9不支持classList ，因此，如果需要IE9支持，則肯定要建立一個后備。