Question

我在PHP中丢失会话变量时遇到了很多麻烦。我发现了很多很好的信息，但在这种情况下没有任何帮助我。这是我的PHP文件：

首先，util.php。它包含在每个文件的顶部。它有session_start（）命令和MySQL连接字符串：

<?php
    session_start();
    $connect=mysqli_connect("localhost","mysql","mypassword","mydb");
    if(mysqli_connect_errno()){
        echo 'Failed to connect to database ' . mysqli_connect_error();
    }
?>

接下来，show_variables.php。它在屏幕上转储所有会话变量：

<?php
echo date('H:i:s');
echo "<br/><p>Session Variables:</p>";
foreach ($_SESSION as $key=>$val)
    echo $key." ".$val."<br/>";
echo session_name();
?>

现在是第一页，index.php。页面顶部从数据库表中提取员工姓名。正文提供了一个包含员工姓名和两个角色的表单。页面根据选择的角色重定向。

<?php
    include "util.php";
    $query=mysqli_query($connect,"select * from staff");
    while ($row = mysqli_fetch_array($query)){
        $staff_select .= '<option value="'.$row[id].'">'.$row[name_first].' '.$row[name_last].'</option>';
    }
?>
<html>
<head>
    <title>Restaurant Order Tracking</title>
    <link href="./css/style.css" rel="stylesheet" type="text/css">
    <script language="javascript" type="text/javascript">
        function start_shift(){
            var e_select = document.selector.employee_select;
            var name = e_select.options[e_select.selectedIndex].value;
            var r_select = document.selector.role_select;
            var role = r_select.options[r_select.selectedIndex].value;
            alert("Ok, " + name + ". You're a " + role + " today. Let's get to work.");
            if(role == "server"){location = "./server/server.php?id=" + name};
            if(role == "foodprep"){location = "foodprep.php?id=" + name};
        }
    </script>
</head>
<body>
    <div id="header">
        <h1>Welcome To The Restaurant Order Tracker</h1>
    </div>
    <div id="middle">
        <p>Now get to work !</p>
        <form name="selector">
            <p>Select your employee:</p>
            <select name="employee_select">
                <?php
                  echo $staff_select;
                ?>
            </select>
            <p>Select your role for today</p>
            <select name="role_select">
                <option value="server">Server</option>
                <option value="foodprep">Food Prep</option>
            </select>
            <br/>
            <input type="button" value="Start Shift" onclick="start_shift()"/>
        </form>
    <?php include "show_variables.php";?>
    </div>
</body>
</html>

此页面正常。在这里选择服务器会导致“server.php”。这是该文件：

<?php
    include "../util.php";
    $_SESSION['id']=$id=$_GET['id'];
    $_SESSION['foo']="fubar";
    $query = mysqli_query($connect,"select name_first, name_last from staff where id = $id");
    while($row = mysqli_fetch_array($query)){
        $_SESSION['name'] = $row['name_first'].' '.$row['name_last'];
        }
?>
<html>
<head>
    <Title>Server Interface</Title>
    <link href="../css/style.css" rel="stylesheet" type="text/css">
    <script language="JavaScript" type="text/javascript">
        function update(target){
            var ajaxRequest;
            ajaxRequest = new XMLHttpRequest();
            ajaxRequest.onreadystatechange = function(){
                if(ajaxRequest.readyState == 4){
                    var middleDisplay = document.getElementById('middle');
                    middleDisplay.innerHTML = ajaxRequest.responseText;
                    }
                }
            ajaxRequest.open("GET", target, true);
            ajaxRequest.send(null);
        }
    </script>
</head>
<body>
    <div id="header">
        <p>Server Interface</p>
        <p>Server Name: <?php echo $_SESSION['name'] ?>  </p>
        <form action="../logout.php" method="post">
        <input type="submit" value="Logout">
        </form>
    </div>
    <div id="middle">
        <?php include "stage1.php" ?>
    </div>
</body>
</html>

此页面设置三个变量：id，name和foo。正如所料，show_variable.php具有以下输出：

19:54:34
Session Variables:
id 2
foo fubar
name Dave Smith
PHPSESSID

中间div还有stage1.php的包含。这是该文件：

<br/>
<form name="selector">
    <input type="button" value="Start a new order" name="new_order" onclick = "update('new_order.php')" />
    <input type="button" value="View your open orders" name="view_order" onclick="update('view_order.php')" />
</form>
<?php include "../show_variables.php"; ?>

到目前为止，这么好。有一些AJAX来改变中间div，这很有效。如果用户选择“开始新订单”，则AJAX将new_order.php放在中间div中。这是该文件：

<?php
    include "../util.php";
    $query=mysqli_query($connect,"select * from loc");
    while ($row = mysqli_fetch_array($query)){
        $table_select .= '<option value="'.$row[id].'">'.$row[description].'</option>';
    }
    echo "<br/>
    <form name = 'new_order'>
    <label>Enter the table number for this order</label>
        <select name = 'table_select'>
            $table_select
        </select>
        <br/>
        <input type='button' value='Start New Order' onclick=\"update('enter_order.php?table=' + document.new_order.table_select[document.new_order.table_select.selectedIndex].value)\" />
        <br/>
        <input type='button' value='Cancel New Order' onclick=\"update('stage1.php')\" />
    </form>
<a href= "stage1.php">Go back to stage 1 via link</a>
"
?>
<?php include "../show_variables.php"; ?>

此页面还显示正确的会话变量：

19:55:27
Session Variables:
id 2
foo fubar
name Dave Smith
PHPSESSID

但在那之后，所有变量都消失了。如果用户单击“取消新订单”，则AJAX脚本会再次使用stage1.php填充中间div。并且会话变量不再存在：

19:59:12
Session Variables:
PHPSESSID

这不能是stage1.php文件中的拼写错误。完全相同的代码在一次查看中具有会话变量，但在另一次查看中丢失它们。我想也许AJAX搞砸了我，所以我把href添加到new_order.php。直接进入stage1.php没有任何AJAX / JavaScript。但是变量又一次丢失了。

我尝试手动输入网址。我浏览http://www.mysite.com/server/server.php?id=1。会话变量正确显示。我打开一个新标签并浏览到http://www.mysite.com/server/server.php（没有获取）。会话变量存在并设置相同。我打开另一个标签并浏览到http://www.mysite.com/server/stage1.php。会话变量不存在。

请注意，每个文件都通过util.php文件具有session_start（）命令。另请注意，这是一个开发服务器。我的网站是唯一的会议。有什么想法吗？

Answer 1

从您发布的代码中不清楚，但在我看来，stage1.php不会调用调用session_start的util.php。

所以stage1.php似乎没有session_start

为避免双重包含，您可以使用include_once

移动到页面后，PHP会话变量丢失

1 个答案: