Loading event (onload)
The event will occur immediately after the page is loaded, and the called program will be executed at the same time.
Note:
When the page is loaded, the onload event is triggered, and the event is written in the <body> tag.
The loading page of this section can be understood as opening a new page.
The following code, when loading a new page, pops up the dialog box "Loading...".
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>php.cn</title>
<script>
function fun(){
window.alert("加载中......")
}
</script>
</head>
<body onload="fun()">
欢迎来到php.cn
</body>
</html>