如下代碼，為什么第一個(gè)函數(shù)也能正確運(yùn)行呢？setInterval()函數(shù)為什么能被聲明為一個(gè)變量呢？
<!DOCTYPE?html?PUBLIC?"-//W3C//DTD?XHTML?1.0?Transitional//EN"?"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html?xmlns="http://www.w3.org/1999/xhtml"?xml:lang="en">
<head>
<meta?http-equiv="Content-Type"?content="text/html;charset=UTF-8">
<title></title>
<script?type="text/javascript">
var?n?=?0;
function?t()?{
document.title?=?n++;
}
var?timer?=?setInterval("t()",1000);
function?h()?{
document.write(9);
}
???setTimeout(h(),1000);
</script>
</head>
<body>
</body>
</html>
javascript的函數(shù)問(wèn)題
fenkapian
2016-07-03 15:19:46
