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javascript-添加到购物车功能在尝试添加产品数量时不起作用

spring-mvc html javascript

-1

Assaf · 技术社区 · 6 年前

下面是java脚本代码,以及相关的html- 问题是-函数只返回第一个按钮的值,而不返回相关按钮的值。

下面的代码只返回表的第一个值。当客户选择第二个产品时,代码不返回任何内容,或者再次返回第一个产品。

我附上了屏幕截图和它的样子。抱歉,代码太长了,如果我没有包括所有的css,屏幕看起来就不一样了。 我想工作的那一排是169号 .

    <!DOCTYPE html>
<html xmlns:th="http://www.w3.org/1999/xhtml">
<head>
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
    <style>
        * {box-sizing: border-box;}

        body {
            margin: 0;
            font-family: Arial, Helvetica, sans-serif;
        }

        .topnav {
            overflow: hidden;
            background-color: #e9e9e9;
        }

        .topnav a {
            float: left;
            display: block;
            color: black;
            text-align: center;
            padding: 14px 16px;
            text-decoration: none;
            font-size: 17px;
        }
        .topnav .proceed {
            float: right;
            display: block;
            color: white;
            background-color: #2196F3;
            text-align: center;
            padding: 14px 16px;
            text-decoration: none;
            font-size: 17px;
        }

        .topnav a:hover {
            background-color: #ddd;
            color: black;
        }

        .topnav a.active {
            background-color: #2196F3;
            color: white;
        }

        .topnav .search-container {
            float: right;
        }

        .topnav input[type=text] {
            padding: 6px;
            margin-top: 8px;
            font-size: 17px;
            border: none;
        }

        .topnav .search-container button {
            float: right;
            padding: 6px 10px;
            margin-top: 8px;
            margin-right: 16px;
            background: #ddd;
            font-size: 17px;
            border: none;
            cursor: pointer;
        }

        .topnav .search-container button:hover {
            background: #ccc;
        }

        @media screen and (max-width: 600px) {
            .topnav .search-container {
                float: none;
            }
            .topnav a, .topnav input[type=text], .topnav .search-container button {
                float: none;
                display: block;
                text-align: left;
                width: 100%;
                margin: 0;
                padding: 14px;
            }
            .topnav input[type=text] {
                border: 1px solid #ccc;
            }
        }
    </style>
</head>
<div class="topnav">
    <a class="active" href="/search">Home</a>
    <a href="/about">About</a>
    <a href="/contact">Contact</a>
    <div class="search-container">
        <form action="/results">
            <input type="text" placeholder="Search.." name="search">
            <button type="submit"><i class="fa fa-search"></i></button>
        </form>
    </div>
</div>

<div style="padding-left:16px">
</div>

<style>
    table {
        border-collapse: collapse;
        border-spacing: 0;
        width: 100%;
        border: 1px solid #ddd;
    }

    th, td {
        text-align: left;
        padding: 16px;
    }

    tr:nth-child(even) {
        background-color: #f2f2f2
    }
</style>
</head>
<body>

<h2>Search Results</h2>
<div class="topnav">
    <a class="proceed" href="/cart">Proceed to checkout</a></div>

<table id="products">
    <tr>
        <th>Product ID</th>
        <th>Name</th>
        <th>Brand</th>
        <th>Rating</th>
        <th>Price</th>
        <th>Availability</th>

        <tr th:each="product : ${results}" class="product">
        <td th:text="${product.productId}" id="productId"></td>
        <td th:text="${product.productName}"></td>
        <td th:text="${product.brand}"></td>
        <td th:text="${product.rating}"></td>
        <td th:text="${product.price}"></td>
        <td th:text="${product.availableInStock}"></td>
        <td><input type="text" placeholder="insert quantity" id="quantity" required></td>
        <td><button onclick="myfunction(this)" class="${product.productId}" type="button">Add to cart</button></td>
        <td><button onclick="myfunction1(this)" class="${product.productId}" type="button">Delete from cart</button></td></tr>
</table>
    <script type="text/javascript">
        function getCookie(cname) {
            var name = cname + "=";
            var decodedCookie = decodeURIComponent(document.cookie);
            var ca = decodedCookie.split(';');
            for(var i = 0; i <ca.length; i++) {
                var c = ca[i];
                while (c.charAt(0) == ' ') {
                    c = c.substring(1);
                }
                if (c.indexOf(name) == 0) {
                    return c.substring(name.length, c.length);
                }
            }
            return "";
        }

        function myfunction(btn) {
            var quan = document.getElementById("quantity").value;
            var productid = btn.closest(".product").innerText.split("\t")[0];
            var clientid = getCookie("clientidcookie");
            var xhttp = new XMLHttpRequest();
            xhttp.open("GET","/products_log" + '?user=' + clientid + '&product=' + productid + '&quant=' + quan,true);
            xhttp.send();
            alert("Product added to cart");
        }
        function myfunction1(btn) {
            var productid = btn.closest(".product").innerText.split("\t")[0];
            var clientid = getCookie("clientidcookie");
            var xhttp = new XMLHttpRequest();
            xhttp.open("GET","/delete_log" + '?user=' + clientid + '&product=' + productid,true);
            xhttp.send();
        }
    </script>
</body>
</html>

âvar quan = btn.closest("tr").getElementsByClassName("quantity")[0].value;â

而不是:

                var quan = document.getElementById("quantity").value;

1 回复 | 直到 6 年前

Programmer 6 年前

元素的Id应该是唯一的,所以当您使用 document.getElementById(...)

你可以这样做-

var quan = this.closest('tr').getElementById("quantity").value;