本文最后更新于 128 天前，其中的信息可能已经有所发展或是发生改变。
1、实现效果
用户输入后按回车，输入的内容自动保存，下方会显示记录的条数，鼠标移动到文字所在div上，会显示删除按钮，点击按钮，相应记录会被删除，下方的记录条数会相应变化，点击clear，所有记录会被删除。效果如下：
2、实现思路
- 先写出记事本的基本样式，在vue实例中的data对象里定义list数组，以及message的初始值。通过 v-model实现input标签文本和message的双向绑定。通过v-for循环遍历li标签，取出list数组中的数据。
- 给input框通过keyup.enter绑定回车事件add，直接把当前输入的值添加到list数组里，然后遍历到li标签里。
- 在li标签的button标签里添加remove事件。先传入index，通过this.list.splice(index, 1) 删除当前记录。
- 在下方的footer部分，判断是否存在记录，若不存在，则销毁标签，若存在，则添加clear事件，直接把list数组赋值为空，就可以清除所有的记录。
3、实现代码
index.css
代码语言：javascript复制html,
body {
margin: 0;
padding: 0;
}
body {
background: #fff;
}
button {
margin: 0;
padding: 0;
border: 0;
background: none;
font-size: 100%;
vertical-align: baseline;
font-family: inherit;
font-weight: inherit;
color: inherit;
-webkit-appearance: none;
appearance: none;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
}
body {
font: 14px "Helvetica Neue", Helvetica, Arial, sans-serif;
line-height: 1.4em;
background: #f5f5f5;
color: #4d4d4d;
min-width: 230px;
max-width: 550px;
margin: 0 auto;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
font-weight: 300;
}
:focus {
outline: 0;
}
.hidden {
display: none;
}
#todoapp {
background: #fff;
margin: 180px 0 40px 0;
position: relative;
box-shadow: 0 2px 4px 0 rgba(0, 0, 0, 0.2), 0 25px 50px 0 rgba(0, 0, 0, 0.1);
}
#todoapp input::-webkit-input-placeholder {
font-style: italic;
font-weight: 300;
color: #e6e6e6;
}
#todoapp input::-moz-placeholder {
font-style: italic;
font-weight: 300;
color: #e6e6e6;
}
#todoapp input::input-placeholder {
font-style: italic;
font-weight: 300;
color: gray;
}
#todoapp h1 {
position: absolute;
top: -160px;
width: 100%;
font-size: 60px;
font-weight: 100;
text-align: center;
color: rgba(175, 47, 47, .8);
-webkit-text-rendering: optimizeLegibility;
-moz-text-rendering: optimizeLegibility;
text-rendering: optimizeLegibility;
}
.new-todo,
.edit {
position: relative;
margin: 0;
width: 100%;
font-size: 24px;
font-family: inherit;
font-weight: inherit;
line-height: 1.4em;
border: 0;
color: inherit;
padding: 6px;
border: 1px solid #999;
box-shadow: inset 0 -1px 5px 0 rgba(0, 0, 0, 0.2);
box-sizing: border-box;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
}
.new-todo {
padding: 16px;
border: none;
background: rgba(0, 0, 0, 0.003);
box-shadow: inset 0 -2px 1px rgba(0, 0, 0, 0.03);
}
.main {
position: relative;
z-index: 2;
border-top: 1px solid #e6e6e6;
}
.toggle-all {
width: 1px;
height: 1px;
border: none; /* Mobile Safari */
opacity: 0;
position: absolute;
right: 100%;
bottom: 100%;
}
.toggle-all label {
width: 60px;
height: 34px;
font-size: 0;
position: absolute;
top: -52px;
left: -13px;
-webkit-transform: rotate(90deg);
transform: rotate(90deg);
}
.toggle-all label:before {
content: "❯";
font-size: 22px;
color: #e6e6e6;
padding: 10px 27px 10px 27px;
}
.toggle-all:checked label:before {
color: #737373;
}
.todo-list {
margin: 0;
padding: 0;
list-style: none;
max-height: 420px;
overflow: auto;
}
.todo-list li {
position: relative;
font-size: 24px;
border-bottom: 1px solid #ededed;
height: 60px;
box-sizing: border-box;
}
.todo-list li:last-child {
border-bottom: none;
}
.todo-list .view .index {
position: absolute;
color: gray;
left: 10px;
top: 20px;
font-size: 16px;
}
.todo-list li .toggle {
text-align: center;
width: 40px;
/* auto, since non-WebKit browsers doesn't support input styling */
height: auto;
position: absolute;
top: 0;
bottom: 0;
margin: auto 0;
border: none; /* Mobile Safari */
-webkit-appearance: none;
appearance: none;
}
.todo-list li .toggle {
opacity: 0;
}
.todo-list li .toggle label {
/*
Firefox requires `#` to be escaped - https://bugzilla.mozilla.org/show_bug.cgi?id=922433
IE and Edge requires *everything* to be escaped to render, so we do that instead of just the `#` - https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/7157459/
*/
background-image: url("data:image/svg xml;utf8,");
background-repeat: no-repeat;
background-position: center left;
}
.todo-list li .toggle:checked label {
background-image: url("data:image/svg xml;utf8,");
}
.todo-list li label {
word-break: break-all;
padding: 15px 15px 15px 60px;
display: block;
line-height: 1.2;
transition: color 0.4s;
}
.todo-list li.completed label {
color: #d9d9d9;
text-decoration: line-through;
}
.todo-list li .destroy {
display: none;
position: absolute;
top: 0;
right: 10px;
bottom: 0;
width: 40px;
height: 40px;
margin: auto 0;
font-size: 30px;
color: #cc9a9a;
margin-bottom: 11px;
transition: color 0.2s ease-out;
}
.todo-list li .destroy:hover {
color: #af5b5e;
}
.todo-list li .destroy:after {
content: "×";
}
.todo-list li:hover .destroy {
display: block;
}
.todo-list li .edit {
display: none;
}
.todo-list li.editing:last-child {
margin-bottom: -1px;
}
.footer {
color: #777;
padding: 10px 15px;
height: 20px;
text-align: center;
border-top: 1px solid #e6e6e6;
}
.footer:before {
content: "";
position: absolute;
right: 0;
bottom: 0;
left: 0;
height: 50px;
overflow: hidden;
box-shadow: 0 1px 1px rgba(0, 0, 0, 0.2), 0 8px 0 -3px #f6f6f6,
0 9px 1px -3px rgba(0, 0, 0, 0.2), 0 16px 0 -6px #f6f6f6,
0 17px 2px -6px rgba(0, 0, 0, 0.2);
}
.todo-count {
float: left;
text-align: left;
}
.todo-count strong {
font-weight: 300;
}
.filters {
margin: 0;
padding: 0;
list-style: none;
position: absolute;
right: 0;
left: 0;
}
.filters li {
display: inline;
}
.filters li a {
color: inherit;
margin: 3px;
padding: 3px 7px;
text-decoration: none;
border: 1px solid transparent;
border-radius: 3px;
}
.filters li a:hover {
border-color: rgba(175, 47, 47, 0.1);
}
.filters li a.selected {
border-color: rgba(175, 47, 47, 0.2);
}
.clear-completed,
html .clear-completed:active {
float: right;
position: relative;
line-height: 20px;
text-decoration: none;
cursor: pointer;
}
.clear-completed:hover {
text-decoration: underline;
}
.info {
margin: 50px auto 0;
color: #bfbfbf;
font-size: 15px;
text-shadow: 0 1px 0 rgba(255, 255, 255, 0.5);
text-align: center;
}
.info p {
line-height: 1;
}
.info a {
color: inherit;
text-decoration: none;
font-weight: 400;
}
.info a:hover {
text-decoration: underline;
}
/*
Hack to remove background from Mobile Safari.
Can't use it globally since it destroys checkboxes in Firefox
*/
@media screen and (-webkit-min-device-pixel-ratio: 0) {
.toggle-all,
.todo-list li .toggle {
background: none;
}
.todo-list li .toggle {
height: 40px;
}
}
@media (max-width: 430px) {
.footer {
height: 50px;
}
.filters {
bottom: 10px;
}
}html与Vue部分
代码语言：javascript复制<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>记事本</title>
</head>
<link rel="stylesheet" type="text/css" href="index.css" />
<body>
<!-- 主体区域 -->
<section id="todoapp">
<!-- 输入框 -->
<header class="header">
<h1>记事本</h1>
<input autofocus="autofocus" autocomplete="off" placeholder="请输入任务" class="new-todo" v-model="message"
@keyup.enter="add" />
</header>
<!-- 列表区域 -->
<section class="main">
<ul class="todo-list">
<li class="todo" v-for="(item,index) in list">
<div class="view">
<span class="index">{{ index 1 }}.</span>
<label>{{ item }}</label>
<button class="destroy" @click="remove(index)"></button>
</div>
</li>
</ul>
</section>
<!-- 统计和清空 -->
<footer class="footer" v-show="list.length!=0">
<span class="todo-count" v-if="list.length!=0">
<strong>{{list.length}}</strong> items left
</span>
<button class="clear-completed" @click="clear">
Clear
</button>
</footer>
</section>
</body>
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
<script>
let vm = new Vue({
el: "#todoapp",
data: {
list: ["努力向前看", "今日事，今日毕", "好读书，读好书"],
message: "please input",
},
methods: {
add() {
this.list.push(this.message)
},
remove(index) {
this.list.splice(index, 1);
},
clear() {
this.list = [];
}
}
})
</script>
</html>
