abstract：<!DOCTYPE html> <html> <head> <meta charset="UTF-8">
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>聊天窗口信息发布，实现最新发布信息显示在顶部</title>
</head>
<body>
<input type="text" name="content">
<button>提交</button>
<ul></ul>
<script>
var input = document.getElementsByName('content').item(0);
var btn = document.getElementsByTagName('button').item(0);
var ul = document.getElementsByTagName('ul').item(0);
//默认进入input获取焦点
input.focus();
//按钮添加点击事件
btn.onclick = function() {
var li = document.createElement('li');
li.innerHTML = input.value;
var len = ul.children.length;
//实现新发布的信息显示在顶部
if (len === 0) {
ul.appendChild(li);
} else {
var first = ul.firstChild;
ul.insertBefore(li, first);
}
//提交完信息，情况输入框和获取焦点
input.value = '';
input.focus();
}
</script>
</body>
</html>
Correcting teacher：灭绝师太Correction time：2019-03-02 14:57:27
Teacher's summary：案例可以跳出老师上课代码哦!希望有个人代码风格