间歇定时器示例
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<div id="box"></div>
<script>
var box = document.getElementById('box');
var num = 10;
box.innerHTML = num;
var timer = setInterval(function(){
num--;
if(num < 0){
num = 0;
clearInterval(timer);
}
box.innerHTML = num;
console.log(num)
},1000)
</script>
</body>
</html>
延时定时器示例
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
#box {
width: 200px;
height: 130px;
position: relative;
position: fixed;
bottom: 0;
right: 0;
display: none;
}
#box img {
width: 100%;
height: 100%;
}
#box span {
position: absolute;
top: 0;
right: 0;
background: red;
color: #fff;
padding: 4px;
cursor: pointer;
}
</style>
</head>
<body>
<div id="box">
<span>X</span>
<img src="images/ad.jpg" alt="">
</div>
<script>
var box = document.getElementById('box');
var close = box.getElementsByTagName('span')[0];
// 出现广告定时器
var timer = setTimeout(function () {
box.style.display = 'block';
clearTimeout(timer);
}, 3000);
// 关闭按钮
close.onclick = function () {
box.style.display = 'none';
setTimeout(function () {
box.style.display = 'block';
}, 3000);
}
</script>
</body>
</html>
