<!DOCTYPE html>
<html lang="en"><head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head><body>
<button>按钮1</button>
<button>按钮2</button>
<button>按钮3</button>
<button>按钮4</button>
<button>按钮5</button> <script>
// 先得到所有按钮,将里面每个按钮遍历出来,分别给每一个按钮添加点击
// 事件,先在事件处理函数中把所有的样式干掉,然后在设置自己的样式
var btn = document.getElementsByTagName("button")
for (let i = 0; i < btn.length; i++) {
btn[i].onclick = function () {
console.log(i);
for (let j = 0; j < btn.length; j++) {
btn[j].style.backgroundColor = ""
}
btn[i].style.backgroundColor = 'pink'
}
}
</script>
</body></html>