<!DOCTYPE HTML>
<html lang="en-US">
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<h2></h2>
<button>clearTimeout</button>
<button>clearInterval</button>
<script type="text/javascript">
var h2 = document.getElementsByTagName('h2')[0];
//获取时间，每隔1s，更新 var t1 = setInterval(function(){
var d1 = new Date();
var y = d1.getFullYear();
var m = d1.getMonth() + 1;
var d = d1.getDate();
var h = d1.getHours();
var i = d1.getMinutes();
var s = d1.getSeconds();
//构造表示时间的字符串
var str = y + "年" + m +"月" + d + "日" + h + "时" + i + "分" + s + "秒";
h2.innerHTML = str;
//写入到h2标签中
},1000); </script> <script type="text/javascript"> function f1(){
console.log('setTimeout');
}
var t1 = window.setTimeout(f1,1000);
console.log( t1 ); var btns = document.getElementsByTagName('button'); btns[0].onclick = function(){
clearTimeout(t1);
} var t2 = setInterval(function(){
console.log( 'setInterval' );
},1500); btns[1].onclick = function(){
clearInterval(t2);
}
</script>
</body>
</html>