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Correction status：Uncorrected
Teacher's comments：
Collection
Collection
随机色的切换：
<!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>随机色</title>
<style>
</style>
</head>
<body>
<button onclick="bg_Color()">随机色</button>
<script>
function bg_Color(){
var bg = "#"
var r = Math.floor(Math.random()*10).toString()+Math.floor(Math.random()*10)
var g = Math.floor(Math.random()*10).toString()+Math.floor(Math.random()*10)
var b = Math.floor(Math.random()*10).toString()+Math.floor(Math.random()*10)
bg+=r+g+b
document.getElementsByTagName('body')[0].style.background = bg;
}
</script>
</body>
</html>点击 "运行实例" 按钮查看在线实例
倒计时的实现：
<!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>倒计时</title>
<style>
p {
height: 50px;
width: 300px;
margin: 100px auto;
}
span {
display: inline-block;
height: 50px;
width: 50px;
line-height: 50px;
font-size: 50px;
color: #f00;
text-align: center;
}
</style>
</head>
<body>
<p>
还剩<span>5</span>秒跳转至
<a href="http://www.php.cn">php中文网</a>
</p>
<script>
var Espan = document.getElementsByTagName('span')[0];
var i = 4;
function fn() {
if (i > 0) {
Espan.innerHTML = i;
i--;
} else {
window.location.href = "http://www.php.cn"
}
}
setInterval("fn()", 1000);
</script>
</body>
</html>点击 "运行实例" 按钮查看在线实例
