<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>计时器</title>
</head>
<script type="text/javascript">
var num=0;
function startCount() {
document.getElementById('count').value=num;
num=num+1;
setTimeout("startCount()",500);
}
//setTimeout(startCount,500);
startCount();
</script>
</head>
<body>
<form>
<input type="text" id="count" />
</form>
</body>
</html>
我在<script>末尾直接调用startCount()函数为什么不能开始运行呢？
2016-05-24
挪一下js的位置，放下面，不然执行js的时候input还没被读出来呢
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>计时器</title>
</head>
</head>
<body>
<form>
<input type="text" id="count" />
</form>
<script type="text/javascript">
var num=0;
function startCount() {
document.getElementById('count').value=num;
num=num+1;
setTimeout("startCount()",500);
}
//setTimeout(startCount,500);
startCount();
</script>
</body>
</html>
举报
