Question

我正在进行一个开放课程项目，我必须通过xml文件加载菜单并跟踪用户购买的内容并将其显示在购物车中。几乎所有事情都已完成，但我似乎无法访问通过$_SESSIONS购买的物品。关于网络如何运行的想法很简单，它使用get变量从菜单中加载特定类别，当一个项目被购买时，我将它作为数组保存在$ _SESSION中但是当我访问cart.php时我不这样做似乎在$_SESSION

中看到了记录

这是我的index.php

<?php
session_start();

//loading the xml file
$dom = simplexml_load_file("../menu.xml");

// variable to store category id
$categoryid;

//to store all the data of a particular category id
$names = [];

//to store the name of the category
$categoryname;

//to count how many categories were in there in the xml file
$categorycount = count($dom->xpath("/menu/category"));

//Checking if the user visited via GET and if GET variable is set
if($_SERVER["REQUEST_METHOD"] == "GET")
{

    if(!isset($_GET["cat"]))
    {
        $categoryid = 1;
    }
    // checking if the variable is set within the limits of number of categories loaded
    else if (isset($_GET["cat"]) && ($_GET["cat"] > 0 && $_GET["cat"] <= $categorycount))
    {
        $categoryid = $_GET["cat"];
    }
    else
    {
        print("invalid category id");
    }

    //now loading the appropriate category from xml
    foreach($dom->xpath("/menu/category[@id = '{$categoryid}']") as $category)
    {
        $categoryname = $category->option;

        //saving the data
        foreach($category->name as $name)
        {
            $names[] = [
                    "optionname" => $name->type,
                    "small" => $name->small,
                    "large" => $name->large,
                    "general" => $name->general
                    ];
        }   
    }

    //loading the displaying files
    include("../views/header.php");
    include("../views/viewpage.php");

}

＆GT;

文件header.php刚刚获得文件的head标记，因此不在此处粘贴，表格由viewpage.php生成，因此其代码如下

<body>
<div class = "cart">
    <a href= "cart.php">View Cart</a>
</div>
<?php if(isset($error)): ?>
<div class = "warning">
    <p>No Item was selected</p>
</div>
<?php endif; ?>
    <table>
        <thead>
            <tr>
                <th colspan = "4"><?= $categoryname ?></th>
            </tr>
            <tr>
                <th>Options</th>
                <th>Small</th>
                <th>Large</th>
                <th>General Price</th>
            </tr>
        </thead>
        <tbody>
            <form action = "buy.php" method = "POST">
                <?php foreach($names as $item): ?>
                <tr class = "even">
                    <td><?= $item["optionname"] ?></td>
                    <td>
                        <!-- checking every key value pair of $item if its empty and dynamically giving the names to inputs combining name and price-->
                        <?php if($item["small"] != ""): ?>
                        <?= $item["small"] ?>
                        <input type = "text" name = "<?= $item["optionname"]?>#<?=$item["small"]?>">
                        </input>
                        <?php endif; ?>
                    </td>
                    <td>
                        <?php if($item["large"] != ""): ?>
                        <?= $item["large"] ?>
                        <input type = "text" name = "<?= $item["optionname"]?>#<?= $item["large"] ?>">
                        </input>
                        <?php endif; ?>
                    </td>
                    <td>
                        <?php if($item["general"] != ""): ?>
                        <?= $item["general"] ?> 
                        <input type = "text" name = "<?= $item["optionname"]?>#<?= $item["general"] ?>">
                        </input>    
                        <?php endif; ?> 
                    </td>
                </tr>
                <?php endforeach ?>

        </tbody>
    </table>

        <input type = "submit" value = "Buy!">
    </form>

    <!-- printing the list to display categories using the categorycount variable-->
    <div class= "list">
        <h4>category</h4>
        <?php
            for($i = 1; $i <= $categorycount; $i++)
            {
                print("<ul>
                        <li><a href = \"?cat={$i}\">{$i}</a></li>
                      </ul>");
            }   
        ?>
    </div>  
</body>

购买过程由buy.php完成，其代码如下

<?php
session_start();
//print_r($_POST);
//print("</br>");

$quantity;
$typename;
$price;
foreach($_POST as $key => $value)
{
    //array to save category name, its size, price and quantity of each item
    $cart = [];

    if(!empty($value))
    {
        $quantity = $value;
        //print($key ." val ". $value);
        //print("</br>");
        //breaking the input name to get the type thats in xml from input name, the section before '#' 
        $typename = strstr($key, "#", true);

        //getting the part that comes after '#'
        $price = substr($key, strpos($key, "#") + 1);

        //now converting the '_' to a space and '.'
        $typename = str_replace("_", " ", $typename);
        $price = str_replace("_", ".", $price);

        //checking if '&' in name is present then convert if to &amp;
        /*if(strpos($typename, "&"))
        {
            $typename = str_replace("&", "&amp;", $typename);
        }*/ 

        //print($typename);
        //print("</br>");
        //print($price);
        //print("</br>");

        //opening the xml file to search
        $dom = simplexml_load_file("../menu.xml");

        //searching
        foreach($dom->xpath("/menu/category") as $category)
        {
            //iterating over every name tag in xml
            foreach($category->name as $name)
            {
                //print("</br>checking on run{$name->type} </br></br>");
                //checking every type tag
                if($name->type == $typename)
                {
                    //storing what category name the type belongs to
                    $cartcategoryname = $category->option;
                    //print("the category is {$cartcategoryname}</br>");

                    //test to see what size the above matched type is
                    if($name->small == $price)
                    {
                        $size = "small";
                    }
                    else if($name->large == $price)
                    {
                        $size = "large";
                    }
                    else
                    {
                        $size = "general";
                    }
                }

            }

            /*adding the name,size,type quantity in an array
             * which would be added to $_SESSION and the array
             * would be wiped clean.*/ 
            $cart = [
                "category" => $cartcategoryname,
                "type" => $typename,
                "size" => $size,
                "price" => $price,
                "quantity" => $quantity
                ];  
        }   

        $_SESSION["cart"][] = $cart;
    }

    /* name of category, its type, size, price and quantity in 
     * arry cart */
    /*$cart[] = [
            "category" => $cartcategoryname,
            "type" => $typename,
            "size" => $size,
            "price" => $price,
            "quantity" => $quantity
            ];*/


    //print_r($cart);
    //print("</br></br></br>");

    //pushing the above created arror into session global
    //$_SESSION["cart"][] = $cart;      
}
//print_r($_SESSION);
//print("</br>");

/*foreach($_SESSION["cart"] as $cartitem)
{
    print($cartitem["category"]."</br>");
    print($cartitem["quantity"]."</br>");
    print($cartitem["type"]."</br>");
}*/ 



$host  = $_SERVER['HTTP_HOST'];
$uri   = rtrim(dirname($_SERVER['PHP_SELF']), '/\\');
$extra = 'index.php?cat=1';
header("Location: http://$host$uri/$extra");
exit;

//header("Location: index.php?cat=1");
//exit;

＆GT;

现在当我在print_r($_SESSION)中使用cart.php时，我无法看到任何事情代码是

<?php
session_start();
foreach($_SESSION["cart"] as $cartitem)
{
    print($cartitem["category"]."</br>");
    print($cartitem["quantity"]."</br>");
    print($cartitem["type"]."</br>");
}
//phpinfo();

＆GT;

xml文件如下

<menu>
<category id = '1'>
    <option>Pizzas</option> 
    <name>
        <type>Tomato &amp; Cheese</type>
        <small>5.50</small>
        <large>9.75</large>
        <general/>
    </name>
    <name>
        <type>Onions</type>
        <small>6.85</small>
        <large>10.85</large>
        <general/>
    </name>
</category>
<category id = '2'>
    <option>Side Orders</option> 
    <name>
        <type>Onion Rings</type>
        <small>2.60</small>
        <large>2.95</large>
        <general/>
    </name>
    <name>
        <type>French Fries</type>
        <small>2.85</small>
        <large>3.85</large>
        <general/>
    </name>
</category>

Answer 1

：

$_SESSION["cart"][] = $cart;中的

buy.php不在（正确的）foreach内。

把它放在最后但是在

之内

foreach($dom->xpath("/menu/category[@id = '{$categoryid}']") as $category)循环。

$cart = [
                "category" => $cartcategoryname,
                "type" => $typename,
                "size" => $size,
                "price" => $price,
                "quantity" => $quantity
                ];  

$_SESSION["cart"][] = $cart;
} // End of foreach($dom->xpath("/menu/category[@id = '{$categoryid}']") as $category)

Answer 2

通过加入$_SESSION，cart.php工作了error_reporting(E_ALL); ini_set("display_errors", 1) 我收到了错误Uncaught exception 'Exception' with message 'Serialization of 'SimpleXMLElement' is not allowed' in [no active file] on line 0 做了一些谷歌搜索，发现xml数据仍然是一个xml数据，需要type cast进入string。这样做让我可以在cart.php

中看到会话变量

如何使用会话显示项目

2 个答案: