Javascript 如何使用计时器和暂停功能创建幻灯片放映/旋转木马

我一直在尝试使用next/undo控制器和函数创建幻灯片，当鼠标进入容器时，它会停止，但当我将鼠标悬停在容器上时，它不会暂停。我正在使用ajax成功初始化startSlide（）。我已经看了一个星期的代码了。找不到错误。请帮忙

 var slideIndex = 1;

var myTimer;

var slideshowContainer;


function startSlide(){
  showSlides(slideIndex);
  myTimer = setInterval(function () { plusSlides(1) }, 7000);
  
  slideshowContainer = document.getElementsByClassName('mySlides')[0];
  slideshowContainer.addEventListener('mouseenter', pause)
  slideshowContainer.addEventListener('mouseleave', resume)
}

这一个是控制幻灯片并使其自动滑动

// NEXT AND PREVIOUS CONTROL
function plusSlides(n) {
  clearInterval(myTimer);
  if (n > 0) {
    showSlides(slideIndex -= 1);
  } else {
    showSlides(slideIndex += 1);
  }

  if (n === -1) {
    myTimer = setInterval(function () { plusSlides(n + 2) }, 4000);
  } else {
    myTimer = setInterval(function () { plusSlides(n + 1) }, 4000);
  }
}

此幻灯片识别当前活动的幻灯片

//Controls the current slide and resets interval if needed
function currentSlide(n) {
  clearInterval(myTimer);
  myTimer = setInterval(function () { plusSlides(n + 1) }, 4000);
  showSlides(slideIndex = n);
}

主要功能

function showSlides(n) {
  var i;
  var slides = document.getElementsByClassName("mySlides");
  var dots = document.getElementsByClassName("dot");
  if (n > slides.length) { slideIndex = 1 }
  if (n < 1) { slideIndex = slides.length }
  for (i = 0; i < slides.length; i++) {
    slides[i].style.display = "none";
  }
  for (i = 0; i < dots.length; i++) {
    dots[i].className = dots[i].className.replace(" active", "");
  }
  slides[slideIndex - 1].style.display = "block";
  dots[slideIndex - 1].className += " active";
}

pause = () => {
  clearInterval(myTimer);
}

resume = () => {
  clearInterval(myTimer);
  myTimer = setInterval(function () { plusSlides(slideIndex) }, 4000);
}