javascript 中的图像转换器

Image changer in javascript

我尝试了很多不同的方法来实现这个。我已经能够使用按钮来更改图像,但是当我添加其余代码以使其自动运行时,我无法让它工作。这是我的代码:

window.onload = function start() {
console.log("started");
slide();
}

function slide() {
console.log("Slide started");
var picNum = 1;
    contStyle = document.getElementById('imgTrans').src;
setInterval(function() {
        if(picNum === 4){
        picNum = 1;
    }
    else{
    switch(picNum){
case 1:
contStyle="images/mints.jpg";
picNum++;
break;
case 2:
contStyle="images/cookies.jpg";
picNum++;
break;
case 3:
contStyle="images/candy.jpg";
picNum++;
break;
case 4:
contStyle="images/cake.jpg";
picNum++;
break;
default:
contStyle="images/cake.jpg";
 }
    }
}, 3000);
 }

那是 JavaScript。这是 html:

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<script src="JS/JS.js"></script>

</head>
<body>
<header>
<h1>Title</h1>
</header>
<nav>
<ul>
<li></li>
</ul>
</nav>
<div>
<h1>My Web Page</h1>

<p id="demo">A Paragraph</p>
<section>
<button type="button" onclick="myFunction()">Try it</button>
<img onchange="changeImage()"id="imgTrans" src="images/cake.jpg">
</section>
 </div>

<footer>
<h6></h6>
</footer>
</body>
</html>

我正在尝试在几个不同的图像之间切换。用于网站主页。(如幻灯片放映)

添加

document.getElementById('imgTrans').src = contStyle;

switch 之后。

然后去掉switch:

function slide() {
  var pictures = [
    "images/mints.jpg", 
    "images/cookies.jpg",
    "images/candy.jpg",
    "images/cake.jpg"
  ];
  var picNum = 0;
  setInterval(function() {
    if (picNum > pictures.length - 1) {
      picNum = 0;
    }

    document.getElementById('imgTrans').src = pictures[picNum];

    picNum++;
  }, 3000);
}