学习目标：
学习内容：
- 事件类型
- 鼠标事件
- 焦点事件
- 键盘事件
- 文本事件
- focus选择器
- 案例
事件类型：
鼠标事件：
<title>事件类型-鼠标事件</title>
<style>
div {
width: 200px;
height: 200px;
background-color: pink;
}
</style>
</head>
<body>
<div></div>
<script>
const div = document.querySelector('div')
div.addEventListener('mouseenter', function () {
console.log(`轻轻的我来了`)
})
div.addEventListener('mouseleave', function () {
console.log(`轻轻的我走了`)
})
</script>
</body>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>练习-轮播图点击切换</title>
<style>
* {
box-sizing: border-box;
}
.slider {
width: 560px;
height: 400px;
overflow: hidden;
}
.slider-wrapper {
width: 100%;
height: 320px;
}
.slider-wrapper img {
width: 100%;
height: 100%;
display: block;
}
.slider-footer {
height: 80px;
background-color: rgb(100, 67, 68);
padding: 12px 12px 0 12px;
position: relative;
}
.slider-footer .toggle {
position: absolute;
right: 0;
top: 12px;
display: flex;
}
.slider-footer .toggle button {
margin-right: 12px;
width: 28px;
height: 28px;
appearance: none;
border: none;
background: rgba(255, 255, 255, 0.1);
color: #fff;
border-radius: 4px;
cursor: pointer;
}
.slider-footer .toggle button:hover {
background: rgba(255, 255, 255, 0.2);
}
.slider-footer p {
margin: 0;
color: #fff;
font-size: 18px;
margin-bottom: 10px;
}
.slider-indicator {
margin: 0;
padding: 0;
list-style: none;
display: flex;
align-items: center;
}
.slider-indicator li {
width: 8px;
height: 8px;
margin: 4px;
border-radius: 50%;
background: #fff;
opacity: 0.4;
cursor: pointer;
}
.slider-indicator li.active {
width: 12px;
height: 12px;
opacity: 1;
}
</style>
</head>
<body>
<div class="slider">
<div class="slider-wrapper">
<img src="./images/slider01.jpg" alt="" />
</div>
<div class="slider-footer">
<p>对人类来说会不会太超前了？</p>
<ul class="slider-indicator">
<li class="active"></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
<li></li>
</ul>
<div class="toggle">
<button class="prev"><</button>
<button class="next">></button>
</div>
</div>
</div>
<script>
const data = [
{ url: './images/slider01.jpg', title: '对人类来说会不会太超前了？', color: 'rgb(100, 67, 68)' },
{ url: './images/slider02.jpg', title: '真正的jo厨出现了！', color: 'rgb(36, 31, 33)' },
{ url: './images/slider03.jpg', title: '李玉刚：让世界通过B站看到东方大国文化', color: 'rgb(139, 98, 66)' },
{ url: './images/slider04.jpg', title: '快来分享你的寒假日常吧~', color: 'rgb(67, 90, 92)' },
{ url: './images/slider05.jpg', title: '哔哩哔哩小年YEAH', color: 'rgb(166, 131, 143)' },
{ url: './images/slider06.jpg', title: '一站式解决你的电脑配置问题！！！', color: 'rgb(53, 29, 25)' },
{ url: './images/slider07.jpg', title: '谁不想和小猫咪贴贴呢！', color: 'rgb(99, 72, 114)' },
{ url: './images/slider08.jpg', title: '谁不想和小猫咪贴贴呢！', color: 'rgb(99, 72, 114)' },
]
const img = document.querySelector('.slider-wrapper img')
const p = document.querySelector('.slider-footer p')
const footer = document.querySelector('.slider-footer')
const next = document.querySelector('.next')
let i = 0
next.addEventListener('click', function () {
i++
i = i >= data.length ? 0 : i
toggle()
})
const prev = document.querySelector('.prev')
prev.addEventListener('click', function () {
i--
i = i < 0 ? data.length - 1 : i
toggle()
})
function toggle() {
img.src = data[i].url
p.innerHTML = data[i].title
footer.style.backgroundColor = data[i].color
document.querySelector('.slider-indicator .active').classList.remove('active')
document.querySelector(`.slider-indicator li:nth-child(${i + 1})`).classList.add('active')
}
let timerId = setInterval(function () {
next.click()
}, 1000)
const slider = document.querySelector('.slider')
slider.addEventListener('mouseenter', function () {
clearInterval(timerId)
})
slider.addEventListener('mouseleave', function () {
clearInterval(timerId)
timerId = setInterval(function () {
next.click()
}, 1000)
})
</script>
</body>
</html>
焦点事件：
<title>焦点事件</title>
</head>
<body>
<input type="text">
<script>
const input = document.querySelector('input')
input.addEventListener('focus', function () {
console.log('有焦点触发')
})
input.addEventListener('blur', function () {
console.log('失去焦点触发')
})
</script>
</body>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>练习-小米搜索框案例</title>
<style>
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
ul {
list-style: none;
}
.mi {
position: relative;
width: 223px;
margin: 100px auto;
}
.mi input {
width: 223px;
height: 48px;
padding: 0 10px;
font-size: 14px;
line-height: 48px;
border: 1px solid #e0e0e0;
outline: none;
}
.mi .search {
border: 1px solid #ff6700;
}
.result-list {
display: none;
position: absolute;
left: 0;
top: 48px;
width: 223px;
border: 1px solid #ff6700;
border-top: 0;
background: #fff;
}
.result-list a {
display: block;
padding: 6px 15px;
font-size: 12px;
color: #424242;
text-decoration: none;
}
.result-list a:hover {
background-color: #eee;
}
</style>
<body>
<div class="mi">
<input type="search" placeholder="小米笔记本">
<ul class="result-list">
<li><a href="#">全部商品</a></li>
<li><a href="#">小米11</a></li>
<li><a href="#">小米10S</a></li>
<li><a href="#">小米笔记本</a></li>
<li><a href="#">小米手机</a></li>
<li><a href="#">黑鲨4</a></li>
<li><a href="#">空调</a></li>
</ul>
</div>
<script>
const input = document.querySelector('[type=search]')
const ul = document.querySelector('.result-list')
input.addEventListener('focus', function () {
ul.style.display = 'block'
input.classList.add('search')
})
input.addEventListener('blur', function () {
ul.style.display = 'none'
input.classList.remove('search')
})
</script>
</body>
</html>
键盘事件：
<title>键盘事件</title>
</head>
<body>
<input type="text">
<script>
const input = document.querySelector('input')
input.addEventListener('keydown', function () {
console.log('键盘按下了')
})
input.addEventListener('keyup', function () {
console.log('键盘弹起了')
})
</script>
</body>
文本事件：
<title>文本事件</title>
</head>
<body>
<input type="text">
<script>
const input = document.querySelector('input')
input.addEventListener('input', function () {
console.log(input.value)
})
</script>
</body>
focus选择器：
<title>focus选择器</title>
<style>
input {
width: 200px;
transition: all .3s;
}
input:focus {
width: 300px;
}
</style>
</head>
<body>
<input type="text">
</body>
案例：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>练习-评论字数统计</title>
<style>
.wrapper {
min-width: 400px;
max-width: 800px;
display: flex;
justify-content: flex-end;
}
.avatar {
width: 48px;
height: 48px;
border-radius: 50%;
overflow: hidden;
background: url(./images/avatar.jpg) no-repeat center / cover;
margin-right: 20px;
}
.wrapper textarea {
outline: none;
border-color: transparent;
resize: none;
background: #f5f5f5;
border-radius: 4px;
flex: 1;
padding: 10px;
transition: all 0.5s;
height: 30px;
}
.wrapper textarea:focus {
border-color: #e4e4e4;
background: #fff;
height: 50px;
}
.wrapper button {
background: #00aeec;
color: #fff;
border: none;
border-radius: 4px;
margin-left: 10px;
width: 70px;
cursor: pointer;
}
.wrapper .total {
margin-right: 80px;
color: #999;
margin-top: 5px;
opacity: 0;
transition: all 0.5s;
}
.list {
min-width: 400px;
max-width: 800px;
display: flex;
}
.list .item {
width: 100%;
display: flex;
}
.list .item .info {
flex: 1;
border-bottom: 1px dashed #e4e4e4;
padding-bottom: 10px;
}
.list .item p {
margin: 0;
}
.list .item .name {
color: #FB7299;
font-size: 14px;
font-weight: bold;
}
.list .item .text {
color: #333;
padding: 10px 0;
}
.list .item .time {
color: #999;
font-size: 12px;
}
</style>
</head>
<body>
<div class="wrapper">
<i class="avatar"></i>
<textarea id="tx" placeholder="发一条友善的评论" rows="2" maxlength="200"></textarea>
<button>发布</button>
</div>
<div class="wrapper">
<span class="total">0/200字</span>
</div>
<div class="list">
<div class="item" style="display: none;">
<i class="avatar"></i>
<div class="info">
<p class="name">清风徐来</p>
<p class="text">大家都辛苦啦，感谢各位大大的努力，能圆满完成真是太好了[笑哭][支持]</p>
<p class="time">2022-10-10 20:29:21</p>
</div>
</div>
</div>
<script>
const tx = document.querySelector('#tx')
const total = document.querySelector('.total')
tx.addEventListener('focus', function () {
total.style.opacity = 1
})
tx.addEventListener('blur', function () {
total.style.opacity = 0
})
tx.addEventListener('input', function () {
total.innerHTML = `${tx.value.length}/200字`
})
</script>
</body>
</html>
