写一个JavaScript轮播图代码

好的，下面是一个简单的JavaScript轮播图代码，你可以根据需要进行修改：

HTML:

<div class="slideshow-container">
  <div class="slide fade">
    <img src="slide1.jpg">
  </div>
  <div class="slide fade">
    <img src="slide2.jpg">
  </div>
  <div class="slide fade">
    <img src="slide3.jpg">
  </div>
</div>

<div class="dots-container">
  <span class="dot"></span>
  <span class="dot"></span>
  <span class="dot"></span>
</div>

CSS:

.slideshow-container {
  max-width: 1000px;
  position: relative;
  margin: auto;
}

.fade {
  -webkit-animation-name: fade;
  -webkit-animation-duration: 1s;
  animation-name: fade;
  animation-duration: 1s;
}

@-webkit-keyframes fade {
  from {
    opacity: .4
  }
  to {
    opacity: 1
  }
}

@keyframes fade {
  from {
    opacity: .4
  }
  to {
    opacity: 1
  }
}

.dots-container {
  text-align: center;
  margin-top: 20px;
}

.dot {
  height: 15px;
  width: 15px;
  margin: 0 5px;
  border-radius: 50%;
  display: inline-block;
  background-color: #bbb;
}

.active {
  background-color: #717171;
}

JavaScript:

var slideIndex = 1;
showSlides(slideIndex);

// Next/previous controls
function plusSlides(n) {
  showSlides(slideIndex += n);
}

// Thumbnail image controls
function currentSlide(n) {
  showSlides(slideIndex = n);
}

function showSlides(n) {
  var i;
  var slides = document.getElementsByClassName("slide");
  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";
}

这个代码创建了一个基本的轮播图，其中包含三张图片和三个圆点，用户可以点击圆点或箭头来切换图片。你可以根据需要进行修改，例如改变图片数量，调整样式等。