1.jQuery完成购物车全选/不全选
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>jquery购物车全选与不全选</title>
</title>
<link rel="stylesheet" href="style.css" />
<script src="https://cdn.bootcdn.net/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
</head>
<body>
<table>
<caption>
购物车
</caption>
<thead>
<tr>
<!-- 全选复选框 -->
<th><input type="checkbox" name="checkAll" id="check-all" checked /><label for="check-all">全选</label>
</th>
<th>图片</th>
<th>品名</th>
<th>单位</th>
<th>单价/元</th>
<th>数量</th>
<th>金额/元</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1020" checked />
</td>
<td>
<a href=""><img src="images/p1.jpg" alt="" /></a>
</td>
<td>iPhone 11</td>
<td>台</td>
<td class="price">4799</td>
<td><input type="number" min="1" value="1" /></td>
<td class="amount">xxxx</td>
</tr>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1020" checked />
</td>
<td>
<a href=""><img src="images/p2.jpg" alt="" /></a>
</td>
<td>小米pro 11</td>
<td>部</td>
<td class="price">3999</td>
<td><input type="number" min="1" value="2" /></td>
<td class="amount">xxxx</td>
</tr>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1030" checked />
</td>
<td>
<a href=""><img src="images/p3.jpg" alt="" /></a>
</td>
<td>MacBook Pro</td>
<td>台</td>
<td class="price">18999</td>
<td><input type="number" min="1" value="1" /></td>
<td class="amount">xxxx</td>
</tr>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1040" checked />
</td>
<td>
<a href=""><img src="images/p4.jpg" alt="" /></a>
</td>
<td>小米75电视</td>
<td>台</td>
<td class="price">5999</td>
<td><input type="number" min="1" value="2" /></td>
<td class="amount">xxxx</td>
</tr>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1050" checked />
</td>
<td>
<a href=""><img src="images/p5.jpg" alt="" /></a>
</td>
<td>Canon 90D单反</td>
<td>台</td>
<td class="price">9699</td>
<td><input type="number" min="1" value="1" /></td>
<td class="amount">xxxx</td>
</tr>
</tbody>
<tfoot>
<tr style="font-weight: bolder; font-size: 1.2em">
<td colspan="5">总计:</td>
<td id="sum">xxxx</td>
<td id="total-amount">xxxx</td>
</tr>
</tfoot>
</table>
<div style="width: 90%; margin: 10px auto">
<button style="float: right; width: 100px">结算</button>
</div>
<script>
// 1.全选复选框
const checkAll = $("#check-all");
// 2.独立复选框
const checkItems = $("input[name='item']");
// 改变全选,独立复选框也改变
checkAll.change(ev => checkItems.each(function () {
$(this).prop("checked", $(ev.target).is(":checked"));
}))
// 改变独立复选框,改变全选
checkItems.change(() => checkAll.prop("checked", [...checkItems].every(item => item.checked)));
</script>
</body>
</html>
2.勾选/不勾选商品时购物车自动完成计算
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>购物车勾选不勾选时自动完成计算</title>
<link rel="stylesheet" href="style.css" />
</head>
<body>
<table>
<caption>
购物车
</caption>
<thead>
<tr>
<!-- 全选复选框 -->
<th><input type="checkbox" name="checkAll" id="check-all" checked /><label for="check-all">全选</label>
</th>
<th>图片</th>
<th>品名</th>
<th>单位</th>
<th>单价/元</th>
<th>数量</th>
<th>金额/元</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1020" checked />
</td>
<td>
<a href=""><img src="images/p1.jpg" alt="" /></a>
</td>
<td>iPhone 11</td>
<td>台</td>
<td class="price">4799</td>
<td><input type="number" min="1" value="1" /></td>
<td class="amount">xxxx</td>
</tr>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1020" checked />
</td>
<td>
<a href=""><img src="images/p2.jpg" alt="" /></a>
</td>
<td>小米pro 11</td>
<td>部</td>
<td class="price">3999</td>
<td><input type="number" min="1" value="2" /></td>
<td class="amount">xxxx</td>
</tr>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1030" checked />
</td>
<td>
<a href=""><img src="images/p3.jpg" alt="" /></a>
</td>
<td>MacBook Pro</td>
<td>台</td>
<td class="price">18999</td>
<td><input type="number" min="1" value="1" /></td>
<td class="amount">xxxx</td>
</tr>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1040" checked />
</td>
<td>
<a href=""><img src="images/p4.jpg" alt="" /></a>
</td>
<td>小米75电视</td>
<td>台</td>
<td class="price">5999</td>
<td><input type="number" min="1" value="2" /></td>
<td class="amount">xxxx</td>
</tr>
<tr>
<td>
<input type="checkbox" name="item" value="SN-1050" checked />
</td>
<td>
<a href=""><img src="images/p5.jpg" alt="" /></a>
</td>
<td>Canon 90D单反</td>
<td>台</td>
<td class="price">9699</td>
<td><input type="number" min="1" value="1" /></td>
<td class="amount">xxxx</td>
</tr>
</tbody>
<tfoot>
<tr style="font-weight: bolder; font-size: 1.2em">
<td colspan="5">总计:</td>
<td id="sum">xxxx</td>
<td id="total-amount">xxxx</td>
</tr>
</tfoot>
</table>
<div style="width: 90%; margin: 10px auto">
<button style="float: right; width: 100px">结算</button>
</div>
<script>
// 全选复选框
const checkAll = document.getElementById("check-all");
const checkItems = document.getElementsByName("item");
// 改变全选,独立复选框也改变
checkAll.onchange = ev => checkItems.forEach(item => item.checked = ev.target.checked);
// 改变独立复选框,改变全选
checkItems.forEach(item => item.onchange = () => checkAll.checked = [...checkItems].every(ele => ele.checked));
// 购物车,自动计算
function cart() {
// 独立单价组
let priceArr = [...document.getElementsByClassName("price")].map(p => p.textContent * 1);
// 独立数量数组
let numbersArr = [...document.querySelectorAll("input[type='number']")].map(n => n.value * 1);
// 独立金额数组
let aumoutsArr = [priceArr, numbersArr].reduce((total, curr) => total.map((item, i) => item * curr[i]));
// 独立金额数据填充,由单品数量改变时触发,与独立复选框状态无关
document.querySelectorAll(".amount").forEach((ele, i) => (ele.textContent = aumoutsArr[i]));
// 获取所有独立复选框元素
let items = document.getElementsByName("item");
// 过滤出所有独立复选框选中状态的数量数组
numbersArr = numbersArr.filter((ele, i) => [...items][i].checked);
// 过滤出所有独立复选框选中状态的金额数组
aumoutsArr = aumoutsArr.filter((ele, i) => [...items][i].checked);
// 计算总数量和总金额
let sum = numbersArr.reduce((pre, cur) => pre + cur, 0);
let total = aumoutsArr.reduce((pre, cur) => pre + cur, 0);
// 填充总数量和总金额到页面中
document.getElementById("sum").textContent = sum;
document.getElementById("total-amount").textContent = total;
}
// 改变单品数量时触发
document.querySelectorAll("input[type='number']").forEach(ele => ele.onchange = cart);
// 改变独立复选框状态时触发
document.getElementsByName("item").forEach(item => item.onchange = cart);
// 全选状态改变时触发
document.getElementById("check-all").addEventListener("change", cart);
// 页面载入完成时加载
window.onload = cart;
</script>
</body>
</html>