核心思路: 点击按钮之后,就动态创建一个li,添加到ul 里面;
创建li 的同时,把文本域里面的值通过li.innerHTML 赋值给 li;
如果想要新的留言后面显示就用 appendChild 如果想要前面显示就用insertBefore;
<!DOCTYPE html>
<html lang="en">
<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>Document</title>
</head>
<body>
<textarea name="" id="" cols="30" rows="10"></textarea>
<button>按钮</button>
<ul></ul>
<script>
var txt = document.querySelector('textarea');
var btn = document.querySelector('button');
var ul = document.querySelector('ul');
btn.onclick = function() {
if (txt.value == '') {
alert('不能为空');
return false;
} else {
var li = document.createElement('li');
li.innerHTML = txt.value + '<a href="javascript:;">删除</a>';
ul.insertBefore(li, ul.children[0]);
var as = document.querySelectorAll('a');
for (var j = 0; j < as.length; j++) {
as[j].onclick = function() {
ul.removeChild(this.parentNode)
}
}
}
}
</script>
</body>
</html>