Mouse over event, when the mouse moves over an object, the object triggers the onmouseover event and executes the program called by the onmouseover event.
Example: When the mouse moves to the element bound to the onmouseover event, a dialog box pops up
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>php.cn</title>
<script>
function fun(){
window.alert("请确认四周没有人再点击提交")
}
</script>
</head>
<body>
<form>
机密：
<input name="txt" type="text" >
<input name="" type="button" value="提交" onmouseover="fun()"/>
</form>
</body>
</html>