Web APIs 第二天

第二天：DOM事件基础，注册事件，tab栏切换

添加事件监听

<body>
    <button>点击</button>
    <script>
        const btn = document.querySelector('button')
        btn.addEventListener('click', function () {
            alert('嗲你')
        })
    </script>
</body>

addEventListener

分为事件源，事件类型，事件处理程序

关闭广告

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box {
            margin: 100px;
            width: 400px;
            height: 200px;
            background-color: pink;
            font-size: 50px;
            text-align: center;

        }

        .box1 {
            position: absolute;
            width: 20px;
            height: 20px;
            background-color: #fff;
            left: 480px;
            top: 120px;
            text-align: center;
            cursor: pointer;
        }
    </style>
</head>

<body>
    <div class="box">广告</div>
    <div class="box1">X</div>

    <script>
        const box1 = document.querySelector('.box1')
        const box = document.querySelector('.box')
        box1.addEventListener('click', function () {
            box.style.display = 'none'
            box1.style.display = 'none'
        })

    </script>
</body>

</html>

事件监听

随机点名

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }

        h2 {
            text-align: center;
        }

        .box {
            width: 600px;
            margin: 50px auto;
            display: flex;
            font-size: 25px;
            line-height: 40px;
        }

        .qs {

            width: 450px;
            height: 40px;
            color: red;

        }

        .btns {
            text-align: center;
        }

        .btns button {
            width: 120px;
            height: 35px;
            margin: 0 50px;
        }
    </style>
</head>

<body>
    <h2>随机点名</h2>
    <div class="box">
        <span>名字是：</span>
        <div class="qs">这里显示姓名</div>
    </div>
    <div class="btns">
        <button class="start">开始</button>
        <button class="end">结束</button>
    </div>

    <script>
        let timerId = 0
        let random = 0
        // 数据数组
        const arr = ['马超', '黄忠', '赵云', '关羽', '张飞']
        const qs = document.querySelector('.qs')
        const start = document.querySelector('.start')

        start.addEventListener('click', function () {
            timerId = setInterval(function () {
                random = parseInt(Math.random() * arr.length)

                qs.innerHTML = arr[random]
            }, 100)
            if (arr.length === 1) {
                start.disabled = true
                end.disabled = true
            }
        })

        const end = document.querySelector('.end')
        end.addEventListener('click', function () {
            clearInterval(timerId)
            arr.splice(random, 1)
        })


    </script>
</body>

</html>

鼠标事件

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</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('我来了');
        })
        div.addEventListener('mouseleave', function () {
            console.log('我走了');
        })
    </script>
</body>

</html>

我来了我走了，鼠标经过事件

焦点事件

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <input type="text" name="" id="">
    <script>
        const input = document.querySelector('input')
        input.addEventListener('focus', function () {
            console.log('触发焦点');

        })

        input.addEventListener('blur', function () {
            console.log('失去焦点');

        })
    </script>
</body>

</html>

小米搜索框

!
<!DOCTYPE html>
<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>Document</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>

</head>

<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

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <input type="text" name="" id="">
    <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>

</html>

键盘按下，键盘弹起

<body>
    <input type="text" name="" id="">
    <script>
        const input = document.querySelector('input')
        input.addEventListener('input', function () {
            console.log(input.value);
        })
    </script>
</body>

文本事件

复选框

<!DOCTYPE html>

<html>

<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }

        table {
            border-collapse: collapse;
            border-spacing: 0;
            border: 1px solid #c0c0c0;
            width: 500px;
            margin: 100px auto;
            text-align: center;
        }

        th {
            background-color: #09c;
            font: bold 16px "微软雅黑";
            color: #fff;
            height: 24px;
        }

        td {
            border: 1px solid #d0d0d0;
            color: #404060;
            padding: 10px;
        }

        .allCheck {
            width: 80px;
        }
    </style>
</head>

<body>
    <table>
        <tr>
            <th class="allCheck">
                <input type="checkbox" name="" id="checkAll"> <span class="all">全选</span>
            </th>
            <th>商品</th>
            <th>商家</th>
            <th>价格</th>
        </tr>
        <tr>
            <td>
                <input type="checkbox" name="check" class="ck">
            </td>
            <td>小米手机</td>
            <td>小米</td>
            <td>￥1999</td>
        </tr>
        <tr>
            <td>
                <input type="checkbox" name="check" class="ck">
            </td>
            <td>小米净水器</td>
            <td>小米</td>
            <td>￥4999</td>
        </tr>
        <tr>
            <td>
                <input type="checkbox" name="check" class="ck">
            </td>
            <td>小米电视</td>
            <td>小米</td>
            <td>￥5999</td>
        </tr>
    </table>
    <script>
        const checkAll = document.querySelector('#checkAll')
        const cks = document.querySelectorAll('.ck')
        checkAll.addEventListener('click', function () {
            //遍历小复选框
            //让小复选框的checked===大复选框checked
            for (let i = 0; i < cks.length; i++) {
                cks[i].checked = checkAll.checked
            }
        })
    </script>
</body>

</html>

事件对象

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <button>点击</button>
    <script>
        const btn = document.querySelector('button')
        btn.addEventListener('click', function (e) {
            console.log(e);

        })
    </script>
</body>

</html>