<!--setTimeout和setInterval区别:setInterval在执行完一次代码之后,经过了那个固定的时间间隔,它还会自动重复执行代码,而setTimeout只执行一次那段代码。-->
/*第一种 用setInterval()*/
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script language="javascript" type="text/javascript">
var i = 4; /*这里不写5,写成4,是为了读秒视觉效果*/
var res;
res = setInterval("jump()", 1000);
function jump()
{
if(i == 0){
window.location.href = 'www.baidu.com';
clearInterval(res);
}
document.getElementById("mes").innerHTML = i;
i--;
}
</script>
</head>
<body>
<div>
<p>将在<span id="mes" style="color: red; font-weight: bold">5</span>秒后跳转...</p>
</div>
</body>
</html>
/*第二种 用setTimeout()*/
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>js读秒跳转setTimeout</title>
<meta http-equiv="refresh" content="5;url=www.baidu.com">
<script language="javascript" type="text/javascript">
var i = 5;
var res;
function jump()
{
document.getElementById("mes").innerHTML = "<font color='red'>" + i + "</font>";
i -= 1;
res = setTimeout("jump()", 1000);
if(i <= 0){
clearTimeout(res);
}
}
window.onload = jump;
</script>
</head>
<body>
<div>
页面将在<span id="mes">5</span>秒后跳转...
</div>
</body>
</html>