![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
Correction status：qualified
Teacher's comments：
Collection
Collection
ToList留言并添加删除功能:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>ToList添加删除功能</title>
</head>
<body>
<h2>留言板</h2>
<input type="text">
<ul></ul>
<script>
var comment = document.querySelector('input');
var ul = document.getElementsByTagName('ul')['0'];
comment.focus(); // 设置焦点
comment.onkeydown = function(event){
if(event.keyCode === 13){
var li = document.createElement('li');
//执行一段空白的javascript语句，返回空或者false值，从而防止链接跳转
li.innerHTML = comment.value+'<a href="javascript:;" onclick="del(this)">' + '删除' + '</a>';
if(ul.childElementCount === 0){
ul.appendChild(li);//向节点添加最后一个子节点
}else{
// 如果列表已有留言,则插入到新一条之前
var first = ul.firstElementChild;
ul.insertBefore(li,first);
}
// 清空留言区,并设置焦点
comment.value = '';
comment.focus();
}
}
function del(ele){
if(confirm('确定要删除么？')){
var li = ele.parentNode;
li.parentNode.removeChild(li);
}
return false;
}
</script>
</body>
</html>点击 "运行实例" 按钮查看在线实例
用js自动生成表格:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>js操作表格的基本技巧</title>
<style>
table,th,td{
border: 1px solid #666;
}
table {
width: 500px;
text-align: center;
border-collapse: collapse;
}
table caption {
font-size: 1.2rem;
margin-bottom: 15px;
}
thead tr:nth-of-type(1) {
background-color: lightblue;
}
</style>
</head>
<body>
<table id="cart">
<caption>购物车</caption>
<thead>
<tr>
<th>编号</th>
<th>品名</th>
<th>数量</th>
<th>单价</th>
</tr>
</thead>
<tbody>
</tbody>
</table>
<script>
var data = [
{id: 1, name: '牛奶', count: 3, price: 50},
{id: 1, name: '苹果', count: 10, price: 80},
{id: 1, name: '衣服', count: 2, price: 600}
];
var car = document.getElementById('cart');
var tbody = car.children[2];
data.forEach(function (value){
var tr = document.createElement('tr');
tr.innerHTML='<td>' + value.id + '</td>';
tr.innerHTML+='<td>' + value.name + '</td>';//追加数据
tr.innerHTML+='<td>' + value.count + '</td>';
tr.innerHTML+='<td>' + value.price + '</td>';
tbody.appendChild(tr);
})
/*var cart = document.getElementById('cart');
var tbody = cart.tBodies[0];
for (var i = 0; i < data.length; i++) {
var tr = document.createElement('tr');
Object.keys(data[i]).forEach(function(key){
tr.innerHTML += '<td>' + data[i][key] + '</td>';
});
tbody.appendChild(tr);
}*/
</script>
</body>
</html>点击 "运行实例" 按钮查看在线实例