javascript詳解實現購物車完整功能(附效果圖，完整代碼)

前言：
我們肯定都很熟悉商品購物車這一功能，每當我們在某寶某東上購買商品的時候，看中了哪件商品，就會加入購物車中，最后結算。購物車這一功能，方便消費者對商品進行管理，可以添加商品，刪除商品，選中購物車中的某一項或幾項商品，最后商品總價也會隨著消費者的操作隨著變化。

一、基本功能

1. 添加商品到購物車
2. 移出購物車中的商品
3. 選中某個商品，動態更新結算價格
4. 商品數量的增加與減少
5. 全選、反選，動態更新結算價格

二、效果圖

1.首頁

包含商品列表，加入購物車按鈕，動態添加商品到購物車

2.添加購物車

點擊按鈕，實現加入購物車功能，商品移入購物車列表項

3.單選或多選商品

點擊左側選擇框，選擇商品，并動態更新總價

4.全選或反選

點擊上方左側按鈕，實現全選，反選功能，并動態更新價格

5.刪除購物車

點擊右側刪除按鈕，出現提示框，點擊確定，刪除購物車的商品，并動態更新價格

三、實現思路

1、用html實現內容
部分關鍵代碼如下，完整代碼見末尾

            <div id="car" class="car">

                <div class="head_row hid">
                    <div class="check left"> <i onclick="checkAll()">√</i></div>
                    <div class="img left">&nbsp;&nbsp;全選</div>
                    <div class="name left">商品名稱</div>
                    <div class="price left">單價</div>
                    <div class="number left">數量</div>
                    <div class="subtotal left">小計</div>
                    <div class="ctrl left">操作</div>
                </div>

            </div>
            <div id="sum_area">
                <div id="pay">去結算</div>
                <div id="pay_amout">合計：<span id="price_num">0</span>元</div>
            </div>

            <div id="box">
                <h3 class="box_head"><span>買購物車中商品的人還買了</span></h3>
                <ul>
                </ul>
            </div>

2、用css修飾外觀

3、用JavaScript(jq)設計動態效果。

第一步：首先是進行html頁面的設計，我用一個大的div(id=box)將所有商品包含，商品列表中我用了ul li實現，接著采用克隆的方式，顯示所有商品列表，具體實現代碼如下

<div id="box">
                <h3 class="box_head"><span>買購物車中商品的人還買了</span></h3>
                <ul>
                </ul>
            </div>

window.onload = function() {
                var aData = [{
                        "imgUrl": "img/03-car-01.png",
                        "proName": " 小米手環4 NFC版 ",
                        "proPrice": "229",
                        "proComm": "1"
                    },
                    {
                        "imgUrl": "img/03-car-02.png",
                        "proName": " Redmi AirDots真無線藍牙耳機 ",
                        "proPrice": "99.9",
                        "proComm": "9.7"
                    },
                    {
                        "imgUrl": "img/03-car-03.png",
                        "proName": " 米家藍牙溫濕度計 ",
                        "proPrice": "65",
                        "proComm": "1.3"
                    },
                    {
                        "imgUrl": "img/03-car-04.png",
                        "proName": " 小米小愛智能鬧鐘 ",
                        "proPrice": "149",
                        "proComm": "1.1"
                    },
                    {
                        "imgUrl": "img/03-car-05.png",
                        "proName": "米家電子溫濕度計Pro  ",
                        "proPrice": "750",
                        "proComm": "0.3"
                    },
                    {
                        "imgUrl": "img/03-car-06.png",
                        "proName": " 小米手環3 NFC版 Pro  ",
                        "proPrice": "199",
                        "proComm": "3.3"
                    },
                    {
                        "imgUrl": "img/03-car-07.png",
                        "proName": " 小米手環3 / 4 通用腕帶",
                        "proPrice": "19.9",
                        "proComm": "1.2"
                    },
                    {
                        "imgUrl": "img/03-car-08.png",
                        "proName": "  米家溫濕度傳感器 ",
                        "proPrice": "45",
                        "proComm": "0.6"
                    },
                    {
                        "imgUrl": "img/03-car-09.png",
                        "proName": "  米家電子溫濕度計Pro 3個裝  ",
                        "proPrice": "207",
                        "proComm": "0.3"
                    },
                    {
                        "imgUrl": "img/03-car-10.png",
                        "proName": " 小米手環3 ",
                        "proPrice": "199",
                        "proComm": "7.2"
                    }
                ];
                var oBox = document.getElementById("box");//商品列表所在的div
                var oUl = document.getElementsByTagName("ul")[0];//商品列表所在的ul
                //遍歷所有商品
                for (var i = 0; i < aData.length; i++) {
                    var oLi = document.createElement("li");
                    var data = aData[i];
                    oLi.innerHTML += '<div class="pro_img"><img src="' + data["imgUrl"] + '" width="150" height="150"></div>';
                    oLi.innerHTML += '<h4 class="pro_name"><a href="#">' + data["proName"] + '</a></h4>';
                    oLi.innerHTML += '<p class="pro_price">' + data["proPrice"] + '元</p>';
                    oLi.innerHTML += '<p class="pro_rank">' + data["proComm"] + '萬人好評</p>';
                    oLi.innerHTML += '<div class="add_btn">加入購物車</div>';
                    oUl.appendChild(oLi);

                }

第二步：給添加購物車按鈕添加事件

    var aBtn = getClass(oBox, "add_btn");//獲取box下的所有添加購物車按鈕
                var number = 0;//初始化商品數量
                for (var i = 0; i < aBtn.length; i++) {
                    number++;
                    aBtn[i].index = i;
                    aBtn[i].onclick = function() {
                        var oDiv = document.createElement("div");
                        var data = aData[this.index];
                        oDiv.className = "row hid";
                        oDiv.innerHTML += '<div class="check left"> <i class="i_check" id="i_check" onclick="i_check()" >√</i></div>';
                        oDiv.innerHTML += '<div class="img left"><img src="' + data["imgUrl"] + '" width="80" height="80"></div>';
                        oDiv.innerHTML += '<div class="name left"><span>' + data["proName"] + '</span></div>';
                        oDiv.innerHTML += '<div class="price left"><span>' + data["proPrice"] + '元</span></div>';
                        oDiv.innerHTML +=' <div class="item_count_i"><div class="num_count"><div class="count_d">-</div><div class="c_num">1</div><div class="count_i">+</div></div> </div>'
                        oDiv.innerHTML += '<div class="subtotal left"><span>' + data["proPrice"] + '元</span></div>'
                        oDiv.innerHTML += '<div class="ctrl left"><a href="javascript:;">×</a></div>';
                        oCar.appendChild(oDiv);
            }
                }

第三步：給商品數量的增加減少的按鈕添加事件

//獲取所有的數量加號按鈕
var i_btn = document.getElementsByClassName("count_i");
                        for (var k = 0; k < i_btn.length; k++) {
                            i_btn[k].onclick = function() {
                                bt = this;
                                //獲取小計節點
                                at = this.parentElement.parentElement.nextElementSibling;
                                //獲取單價節點
                                pt = this.parentElement.parentElement.previousElementSibling;
                                //獲取數量值
                                node = bt.parentNode.childNodes[1];
                                console.log(node);
                                num = node.innerText;
                                num = parseInt(num);
                                num++;
                                node.innerText = num;
                                //獲取單價
                                price = pt.innerText;
                                price = price.substring(0, price.length - 1);
                                //計算小計值
                                at.innerText = price * num + "元";
                                //計算總計值
                                getAmount();
                            }
                        }
                        //獲取所有的數量減號按鈕
                        var d_btn = document.getElementsByClassName("count_d");
                        for (k = 0; k < i_btn.length; k++) {
                            d_btn[k].onclick = function() {
                                bt = this;
                                //獲取小計節點
                                at = this.parentElement.parentElement.nextElementSibling;
                                //獲取單價節點
                                pt = this.parentElement.parentElement.previousElementSibling;
                                //獲取c_num節點
                                node = bt.parentNode.childNodes[1];
                                num = node.innerText;
                                num = parseInt(num);
                                if (num > 1) {
                                    num--;
                                }
                                node.innerText = num;
                                //獲取單價
                                price = pt.innerText;
                                price = price.substring(0, price.length - 1);
                                //計算小計值     
                                at.innerText = price * num + "元";
                                //計算總計值
                                getAmount();
                            }
                        }

第四步：刪除某個商品

//獲取刪除按鈕，并添加事件
var delBtn = oDiv.lastChild.getElementsByTagName("a")[0];
                        delBtn.onclick = function() {
                            var result = confirm("確定刪除嗎?");
                            if (result) {
                                oCar.removeChild(oDiv);
                                number--;
                                getAmount();
                            }
                        }

第五步：全選
通過類名的添加與刪除，實現選中和非選中功能

var index = false;
            function checkAll() {
                var choose = document.getElementById("car").getElementsByTagName("i");
                // console.log(choose);
                if (choose.length != 1) {
                    for (i = 1; i < choose.length; i++) {
                        if (!index) {
                            choose[0].classList.add("i_acity2")
                            choose[i].classList.add("i_acity");
                        } else {
                            choose[i].classList.remove("i_acity");
                            choose[0].classList.remove("i_acity2")
                        }
                    }
                    index = !index;
                }
                getAmount();
            }

第六步：單選
選中某個或多個商品，首先判斷選中狀態，然后通過類名的添加與刪除，實現選中和非選中功能，

//獲取選中框
var check = oDiv.firstChild.getElementsByTagName("i")[0];
                        check.onclick = function() {
                            // console.log(check.className);
                            if (check.className == "i_check i_acity") {
                                check.classList.remove("i_acity");

                            } else {
                                check.classList.add("i_acity");
                            }
                            getAmount();
                        }

第七步：動態更新總價

            //進行價格合計
            function getAmount() {
                //獲取選中的選擇框
                ns = document.getElementsByClassName("i_acity");
                //初始化總價
                sum = 0;
                //選中框
                document.getElementById("price_num").innerText = sum;
                for (y = 0; y < ns.length; y++) {
                    //小計
                    amount_info = ns[y].parentElement.parentElement.lastElementChild.previousElementSibling;
                    num = parseInt(amount_info.innerText);
                    sum += num;
                    document.getElementById("price_num").innerText = sum;
                }
            }

四、完整代碼實現

注意：圖片地址請自行修改
在線演示地址：點擊進入在線演示
附上下載地址，可以直接運行：點擊進入下載地址

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <link rel="stylesheet" type="text/css" href="css/help-center.css" />
        <title>我的購物車</title>

        <style>
            * {
        margin: 0;
        padding: 0;
        font-family: "微軟雅黑";
        list-style: none;
        color: #666;
        text-decoration: none;
        font-size: 14px;
    }
    body {
        background: #f5f5f5;
        height: 100%;
    }
    .header{
    font-size: 12px;
    border-bottom: 2px solid #ff6700;
    background: #fff;
    color: #b0b0b0;
    position: relative;
    z-index: 20;
    height: 100px;
}
    .header .container {
    position: relative;
    width: 1226px;
    margin-right: auto;
    margin-left: auto;
}
 .header .container .header-logo {
    width: 93px;
    margin-top: 26px;
}

 .logo {
    width: 48px;
    height: 48px;
    position: relative;
    display: block;
    width: 55px;
    height: 55px;
    overflow: hidden;
    background-color: #ff6700;
    }
    .header-title {
    float: left;
    margin-top: 26px;
    font-size: 12px;
    }
    .topbar-info {
    margin-top: 30px;
    line-height: 40px;
}
    .link {
    padding: 0 5px;
    color: #757575;
    text-decoration: none;
    }
    .hid {
        overflow: hidden;
    }
    .left {
        float: left;
    }
    .box_head{
    position: relative;
    margin: 0;
    height: 50px;
    font-size: 30px;
    font-weight: 400;
    color: #757575;
    border-top: 1px solid #e0e0e0;
  }
  .box_head span{
  position: absolute;
    top: -20px;
    left: 372px;
    height: 40px;
    width: 482px;
    line-height: 40px;
    text-align: center;
    display: block;
    background-color: #f5f5f5;
    font-size: 30px;
    }
    #box {
        width:1240px;
        margin: 20px auto;
    }
    #box ul {
        margin-right: -14px;
        overflow: hidden;
    }
    #box li {
        width: 234px;
        float: left;
        margin-right: 14px;
        padding: 24px 0 20px;
        background: #FFF;
        text-align: center;
        position: relative;
        cursor: pointer;
        margin-bottom:14px;
    }
    .pro_img {
        width: 150px;
        height: 150px;
        margin: 0 auto 18px;
    }
    .pro_name {
        display: block;
        text-overflow: ellipsis;
        white-space: nowrap;
        overflow: hidden;
        font-weight: 400;
    }
    .pro_name a {
        color: #333;
    }
    .pro_price {
        color: #ff6700;
        margin: 10px;
    }
    .pro_rank {
        color: #757575;
        margin: 10px;
    }
    #box li:hover .add_btn {
        display: block;
    }
    #box li:hover .pro_rank {
        opacity: 0;
    }
    #box li .add_btn:hover {
        background-color: #f60;
        color: white;
    }

    .add_btn {
        height: 22px;
        position: absolute;
        width: 122px;
        bottom: 28px;
        left: 50%;
        margin-left: -61px;
        line-height: 22px;
        display: none;
        color: #F60;
        font-size: 12px;
        border: 1px solid  #f60;
    }
    .car {
        width: 1240px;
        margin: 20px auto;
        background: #FFF;
    }
    .car .check{
        width: 50px;

    }
    .car .check i{
        color: #fff;
        display: inline-block;

        width: 18px;
        height: 18px;
        line-height: 18px;
        border: 1px solid #e0e0e0;
        margin-left: 24px;
        background-color: #fff;
        font-size: 16px;
        text-align: center;
        vertical-align: middle;
        position: relative;
        top: -1px;
        cursor: pointer;
        font-family: "iconfont";
    }
    .i_acity {

        border-color: #ff6700 !important;
        background-color: #ff6700 !important;
    }
    .car .img {
        width: 190px;
    }
    .car .img img {
        display: block;
        width: 80px;
        height: 80px;
        margin: 3px auto;
    }
    .car .name {
        width: 300px;
    }
    .car .name span {
        line-height: 1;
        margin-top: 8px;
        margin-bottom: 8px;
        font-size: 18px;
        font-weight: normal;
        text-overflow: ellipsis;
        white-space: nowrap;
        overflow: hidden;
    }
    .car .price {
        width: 144px;
        text-align: right;
        padding-right: 84px;
    }
    .car .price span {
        color: #ff6700;
        font-size: 16px;
    }
    .car .number{
        width: 150px;
    }
    .car .subtotal{
        width: 130px;

    }
    .car .ctrl {
        width: 105px;
        padding-right:25px;
        text-align: center;
    }
    .car .ctrl a {
        font-size: 20px;
        cursor: pointer;
        display: block;
        width: 26px;
        height: 26px;
        margin: 30px auto;
        line-height: 26px;
    }
    .car .ctrl a:hover {
        color: #FFF;
        background: #ff6700;
        border-radius: 50%;
    }
    .head_row {
        height: 70px;
        line-height: 70px;
    }
    .head_row, .row {
        border-bottom: solid 1px #e0e0e0;
    }
    .row {
        height: 86px;
        line-height:86px;
        padding: 15px 0;
        margin: 0px;
    }
    #sum_area{
        width:1240px;
        height: 60px;
        background: white;
        margin: 20px auto;
    }
    #sum_area #pay{
        width:250px;
        height:60px;
        text-align: center;
        float: right;
        line-height: 60px;
        font-size: 19px;
        background: #FF4B00;
        color: white;
    }
    #sum_area #pay_amout{
        width:250px;
        height:60px;
        text-align: center;
        float: right;
        line-height: 60px;
        font-size: 16px;
        color:#FF4B00 ;
    }
    #sum_area #pay_amout #price_num{
        width:100px;
        height: 60px;
        font-size: 25px;
        color:#FF4B00 ;
    /*  float: left;*/
    }

    .item_count_i{
        height: 85px;
        width:10%;
        /*border: 1px solid black;*/
        float: left;
        margin-right: 25px;
    }
    .num_count{
        width:150px;
        height:40px;
        border: 1.2px solid #E0E0E0;
        float:right;
        margin-top: 21px;

    }
    .count_i{
        width:30%;
        height:40px;
        line-height: 40px;
        float: left;
        text-align: center;
        font-size:21px;
        color: #747474;
    }
    .count_i:hover{
        width:30%;
        height:40px;
        line-height: 40px;
        float: left;
        text-align: center;
        font-size:21px;
        color: #747474;
        background: #E0E0E0;
        cursor: pointer;
    }
    .c_num{
        width:40%;
        height:40px;
        line-height: 40px;
        float: left;
        text-align: center;
        font-size:16px;
        color: #747474;
    }
    .count_d{
        width:30%;
        height:40px;
        line-height: 40px;
        float: left;
        text-align: center;
        font-size:25px;
        color: #747474;
    }
    .count_d:hover{
        width:30%;
        height:40px;
        line-height: 40px;
        float: left;
        text-align: center;
        font-size:25px;
        color: #747474;
        background: #E0E0E0;
        cursor: pointer;
    }
    .i_acity2 {
        border-color: #ff6700 !important;
        background-color: #ff6700 !important;
    }

</style>
    </head>
    <body>
        <script>
            window.onload = function() {
                var aData = [{
                        "imgUrl": "img/03-car-01.png",
                        "proName": " 小米手環4 NFC版 ",
                        "proPrice": "229",
                        "proComm": "1"
                    },
                    {
                        "imgUrl": "img/03-car-02.png",
                        "proName": " Redmi AirDots真無線藍牙耳機 ",
                        "proPrice": "99.9",
                        "proComm": "9.7"
                    },
                    {
                        "imgUrl": "img/03-car-03.png",
                        "proName": " 米家藍牙溫濕度計 ",
                        "proPrice": "65",
                        "proComm": "1.3"
                    },
                    {
                        "imgUrl": "img/03-car-04.png",
                        "proName": " 小米小愛智能鬧鐘 ",
                        "proPrice": "149",
                        "proComm": "1.1"
                    },
                    {
                        "imgUrl": "img/03-car-05.png",
                        "proName": "米家電子溫濕度計Pro  ",
                        "proPrice": "750",
                        "proComm": "0.3"
                    },
                    {
                        "imgUrl": "img/03-car-06.png",
                        "proName": " 小米手環3 NFC版 Pro  ",
                        "proPrice": "199",
                        "proComm": "3.3"
                    },
                    {
                        "imgUrl": "img/03-car-07.png",
                        "proName": " 小米手環3 / 4 通用腕帶",
                        "proPrice": "19.9",
                        "proComm": "1.2"
                    },
                    {
                        "imgUrl": "img/03-car-08.png",
                        "proName": "  米家溫濕度傳感器 ",
                        "proPrice": "45",
                        "proComm": "0.6"
                    },
                    {
                        "imgUrl": "img/03-car-09.png",
                        "proName": "  米家電子溫濕度計Pro 3個裝  ",
                        "proPrice": "207",
                        "proComm": "0.3"
                    },
                    {
                        "imgUrl": "img/03-car-10.png",
                        "proName": " 小米手環3 ",
                        "proPrice": "199",
                        "proComm": "7.2"
                    }
                ];
                var oBox = document.getElementById("box");
                var oCar = document.getElementById("car");
                var oUl = document.getElementsByTagName("ul")[0];

                for (var i = 0; i < aData.length; i++) {
                    var oLi = document.createElement("li");
                    var data = aData[i];

                    oLi.innerHTML += '<div class="pro_img"><img src="' + data["imgUrl"] + '" width="150" height="150"></div>';
                    oLi.innerHTML += '<h4 class="pro_name"><a href="#">' + data["proName"] + '</a></h4>';
                    oLi.innerHTML += '<p class="pro_price">' + data["proPrice"] + '元</p>';
                    oLi.innerHTML += '<p class="pro_rank">' + data["proComm"] + '萬人好評</p>';
                    oLi.innerHTML += '<div class="add_btn">加入購物車</div>';
                    oUl.appendChild(oLi);

                }
                var aBtn = getClass(oBox, "add_btn");//獲取box下的所有添加購物車按鈕
                var number = 0;//初始化商品數量
                for (var i = 0; i < aBtn.length; i++) {
                    number++;
                    aBtn[i].index = i;
                    aBtn[i].onclick = function() {
                        var oDiv = document.createElement("div");
                        var data = aData[this.index];
                        oDiv.className = "row hid";
                        oDiv.innerHTML += '<div class="check left"> <i class="i_check" id="i_check" onclick="i_check()" >√</i></div>';
                        oDiv.innerHTML += '<div class="img left"><img src="' + data["imgUrl"] + '" width="80" height="80"></div>';
                        oDiv.innerHTML += '<div class="name left"><span>' + data["proName"] + '</span></div>';
                        oDiv.innerHTML += '<div class="price left"><span>' + data["proPrice"] + '元</span></div>';
                        oDiv.innerHTML +=' <div class="item_count_i"><div class="num_count"><div class="count_d">-</div><div class="c_num">1</div><div class="count_i">+</div></div> </div>'
                        oDiv.innerHTML += '<div class="subtotal left"><span>' + data["proPrice"] + '元</span></div>'
                        oDiv.innerHTML += '<div class="ctrl left"><a href="javascript:;">×</a></div>';
                        oCar.appendChild(oDiv);
                        var flag = true;
                        var check = oDiv.firstChild.getElementsByTagName("i")[0];
                        check.onclick = function() {
                            // console.log(check.className);
                            if (check.className == "i_check i_acity") {
                                check.classList.remove("i_acity");

                            } else {
                                check.classList.add("i_acity");
                            }
                            getAmount();
                        }
                        var delBtn = oDiv.lastChild.getElementsByTagName("a")[0];
                        delBtn.onclick = function() {
                            var result = confirm("確定刪除嗎?");
                            if (result) {
                                oCar.removeChild(oDiv);
                                number--;
                                getAmount();
                            }
                        }
                        var i_btn = document.getElementsByClassName("count_i");
                        for (var k = 0; k < i_btn.length; k++) {
                            i_btn[k].onclick = function() {
                                bt = this;
                                //獲取小計節點
                                at = this.parentElement.parentElement.nextElementSibling;
                                //獲取單價節點
                                pt = this.parentElement.parentElement.previousElementSibling;
                                //獲取數量值
                                node = bt.parentNode.childNodes[1];
                                console.log(node);
                                num = node.innerText;
                                num = parseInt(num);
                                num++;
                                node.innerText = num;
                                //獲取單價
                                price = pt.innerText;
                                price = price.substring(0, price.length - 1);
                                //計算小計值
                                at.innerText = price * num + "元";
                                //計算總計值
                                getAmount();
                            }
                        }
                        //獲取所有的數量減號按鈕
                        var d_btn = document.getElementsByClassName("count_d");
                        for (k = 0; k < i_btn.length; k++) {
                            d_btn[k].onclick = function() {
                                bt = this;
                                //獲取小計節點
                                at = this.parentElement.parentElement.nextElementSibling;
                                //獲取單價節點
                                pt = this.parentElement.parentElement.previousElementSibling;
                                //獲取c_num節點
                                node = bt.parentNode.childNodes[1];
                                num = node.innerText;
                                num = parseInt(num);
                                if (num > 1) {
                                    num--;
                                }
                                node.innerText = num;
                                //獲取單價
                                price = pt.innerText;
                                price = price.substring(0, price.length - 1);
                                //計算小計值     
                                at.innerText = price * num + "元";
                                //計算總計值
                                getAmount();
                            }
                        }

                        delBtn.onclick = function() {
                            var result = confirm("確定刪除嗎?");
                            if (result) {
                                oCar.removeChild(oDiv);
                                number--;
                                getAmount();
                            }
                        }

                    }
                }

            }

            function getClass(oBox, tagname) {
                var aTag = oBox.getElementsByTagName("*");
                var aBox = [];
                for (var i = 0; i < aTag.length; i++) {
                    if (aTag[i].className == tagname) {
                        aBox.push(aTag[i]);
                    }
                }
                return aBox;
            }

            var index = false;
            function checkAll() {
                var choose = document.getElementById("car").getElementsByTagName("i");
                // console.log(choose);
                if (choose.length != 1) {
                    for (i = 1; i < choose.length; i++) {
                        if (!index) {
                            choose[0].classList.add("i_acity2")
                            choose[i].classList.add("i_acity");
                        } else {
                            choose[i].classList.remove("i_acity");
                            choose[0].classList.remove("i_acity2")
                        }
                    }
                    index = !index;
                }
                getAmount();
            }

            //進行價格合計
            function getAmount() {
                // console.log(ys);
                ns = document.getElementsByClassName("i_acity");
                console.log(ns);
                sum = 0;
                //選中框
                document.getElementById("price_num").innerText = sum;
                for (y = 0; y < ns.length; y++) {
                    //小計
                    amount_info = ns[y].parentElement.parentElement.lastElementChild.previousElementSibling;
                    num = parseInt(amount_info.innerText);
                    sum += num;
                    document.getElementById("price_num").innerText = sum;
                }
            }
        </script>
        </head>
        <body>
            <div class="header">
                <div class="container">
                    <div class="header-logo">
                        <a class="logo ir" href="" title="小米官網">小米官網</a>
                    </div>
                    <div class="header-title" id="J_miniHeaderTitle">
                        <h3 >我的購物車</h3>
                    </div>
                    <div class="topbar-info" id="J_userInfo">
                        <a class="link" >登錄</a><span class="sep">|</span><a class="link" >注冊</a></div>
                </div>
            </div>

            <div id="car" class="car">

                <div class="head_row hid">
                    <div class="check left"> <i onclick="checkAll()">√</i></div>
                    <div class="img left">&nbsp;&nbsp;全選</div>
                    <div class="name left">商品名稱</div>
                    <div class="price left">單價</div>
                    <div class="number left">數量</div>
                    <div class="subtotal left">小計</div>
                    <div class="ctrl left">操作</div>
                </div>

            </div>
            <div id="sum_area">
                <div id="pay">去結算</div>
                <div id="pay_amout">合計：<span id="price_num">0</span>元</div>
            </div>

            <div id="box">
                <h3 class="box_head"><span>買購物車中商品的人還買了</span></h3>
                <ul>
                </ul>
            </div>

        </body>
</html>

感謝您的閱讀，有什么問題或者意見歡迎您提出