<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<button>点击1</button>
<button>点击2</button>
<button>点击3</button>
<img src="images/01.png" alt="" id="pic">
<script>
// 点击三个按钮切换图片
// 事件源.事件=function () {
//
// }
var btns=document.getElementsByTagName("button");
var pic=document.getElementById("pic");
for(var i=0;i<btns.length;i++){
btns[i].index=i;//{index:0} {index:1} {index:2}
btns[i].onclick=function () {
pic.src="images/0"+(this.index+1)+".png";
}
}
</script>
</body>
</html>