在Mysqli中使用php會話獲取WHERE信息

Question

我試圖用一個會議通過我的登錄系統設定在約誰沒有填寫表格的用戶數據庫中獲取信息。

我現在正在使用的代碼：

<?php
$con=mysqli_connect("127.0.0.1","user","pass","db");
// Check connection
if (mysqli_connect_errno()) {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$result = mysqli_query($con,"SELECT * FROM playerdata WHERE Unique_ID = '$uid'");

while($row = mysqli_fetch_array($result)) {
 $row['Unique_ID'];
 $row['AC'];
?>

<b><?php echo $row['AC']; ?></b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</div>
<?php
}

mysqli_close($con);
?>

<p>&nbsp;</p>
Welcome to the armour coins shop! Here you can spend your hard earned coins on some shiny armour and weapons. You gain coins by leveling up in-game. You can do this by preforming laberous activities. <a href="?explain=leveling">Click here for more information about leveling</a>
<p>&nbsp;</p>                           
<form action="buy.php" method="POST" class="form-inline" style="display:inline-block;">
<input type="hidden" name="uid" value="<?php echo $_POST['uid']; ?>">
<input type="hidden" name="username" value="<?php echo $_POST['username']; ?>">
<input type="hidden" name="item" value="127">
<input type="submit" value="Buy Brynie">

<?php
}
elseif(!empty($_POST['username']) && !empty($_POST['password']))
{
     $username = mysql_real_escape_string($_POST['username']);
    $password = mysql_real_escape_string($_POST['password']);
     $uid = mysql_real_escape_string($_POST['uid']);

     $checklogin = mysql_query("SELECT * FROM account WHERE Username = '".$username."' AND Password = '".$password."' AND Unique_ID = '".$uid."'");

    if(mysql_num_rows($checklogin) == 1)
    {
         $row = mysql_fetch_array($checklogin);
        $email = $row['EmailAddress'];

        $_SESSION['Username'] = $username;
        $_SESSION['Uid'] = $uid;
        $_SESSION['EmailAddress'] = $email;
        $_SESSION['LoggedIn'] = 1;
        ?>

如您所見，我正在使用會話，但是我想根據用戶在數據庫中獲取信息。

這不起作用：

$uid = ($_SESSION['Uid']) ?>

$result = mysqli_query($con,"SELECT * FROM playerdata WHERE Unique_ID = '$uid'");

Answer 1

我看不到您的代碼中的session_start（），您需要先添加session_start（）才能使用會話http://www.php.net/manual/zh/function.session-start.php