当js中有window.onload，而BODY标签中又有onload属性时
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>当js中有window.onload，而<BODY>中又有onload属性时</title>
<link rel="stylesheet" type="text/css" href="body.css" target="_blank" rel="external nofollow" >
<script type="text/javascript">
alert('a');
window.onload=fn;//打印acb // 后续脚本不执行
//window.onload=fn(); //打印abc
/*
window.onload=fn;和window.onload=fn();这2种写法执行的顺序不一样
*/
function fn(){
alert('b');
}
alert('c');
</script>
</head>
<body onload="alert('d');">
</body>
</html>
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