HTML事件处理程序
HTML事件处理称序是将事件写在元素的开始标签，当作属性来用，如下面的单击事件:
<!DOCTYPE html>
<html>
<head>
<title>HTNL事件处理程序</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
</head>
<body>
<button>按钮</button>
<script>
function say)()}{
alrt('HTML事件处理程序');
}
</script>
</body>
</html>