PDO / PHP未定義的變量

Question

我感覺自己犯了語法錯誤。 除了語法錯誤，還是忘記定義一個會導致該錯誤的變量，還有別的嗎？

注意：我現在收到一條錯誤消息，指出它期望使用;。 在包含if ($query->execute(array($user_name))) {

    if (isset($_GET['username'])){
        $user_name = $_GET['user_name'];
        $dbh = connectDb(); 
        $query = $dbh->prepare("SELECT * FROM users WHERE user_name = ?");
        if ($query->execute(array($user_name))) {
            while ($row = $query->fetch(PDO::FETCH_ASSOC)) {
                $email = $row['user_email'];
                $admin = $row['user_access_level'];
                $dbusername = $row['user_name'];
            }
        }
        if ($user_name != $dbusername) {
            echo "There has been a fatal error. Please try again.";
        }
    } else echo "you need to specify a username!";
?>
    <center><h2><?php echo $dbusername; ?>'s Profile</h2><br /></center>
    <table width="350" border="3" align="center" cellpadding="0" cellspacing="1" bgcolor="#000000">
        <tr><td>Username:</td><td><?php echo $user_name; ?></td></tr>
        <tr><td>User Level:</td><td><?php echo $userlvl; ?></td></tr>
        <tr><td>Email:</td><td><?php echo $email; ?></td></tr>
    </table>

Answer 1

嘗試這個 ;）

這是一個小錯字問題：

if (isset($_GET['username'])){
  $user_name = $_GET['username']; /* here you are using user_name it should be username or both should be user_name */

Answer 2

$query = $dbh->prepare("SELECT * FROM users WHERE user_name = ?");
if ($query->execute(array($user_name))) {
    while ($row = $query->fetch(PDO::FETCH_ASSOC)) {
        $email = $row['user_email'];
    }
}

您正在尋找類似的東西。 請注意，我在iPhone上，所以很難編碼，哈哈