Question

我想阻止用户注册已在我的表格中设置的电子邮件地址。我是这样做的：

$emailcheck = $bdd->prepare('SELECT COUNT(*) FROM ' . DB_TABLE . ' WHERE MATCH(email) AGAINST '.$_POST['email'].' ');
$emailcheck->execute();
$emailcheckrows = $emailcheck->fetch();

if ($emailcheckrows > 0) {
    $_SESSION['err_msg']="This email address is already registered";
    $error=true;
    $emailcheck->closeCursor();
}

但这不起作用。我已经尝试了几乎所有的东西（也有LIKE，=和in-array）。＆＃34;如果＆＃34;我输入已提交的电子邮件时未执行。

有什么想法吗？谢谢

Answer 1

你可以将它用作一个简单的函数，如：

class Validation {
    public static function emailUnique($conn, $email)
        {
            $sql = "SELECT email FROM formular WHERE email = '".$email."'";
            $emailUnique = $conn->query($sql);
            return (boolean) $emailUnique->num_rows;
        }
}

如果找到条目，则返回true，如果没有，则返回false，然后您可以在脚本中调用此函数。我已经将它与bootstrap-alerts一起使用了：

$errorField = "";
$labelClass = array(
 "emailUnique"=>"",
);
$email = mysqli_real_escape_string($conn, $_POST["email"]);
$errorMessages["emailUnique"] = Validation::emailUnique($conn ,$email);

$DisplayErrorForm = array();
$hasErrors = false;
$formErrorMessage = "";
foreach ($labelClass as $key=>$value) {
          if($errorMessages[$key]){
          $labelClass[$key] = "has-error";
          $hasErrors = true;

          $DisplayErrorForm["emailUnique"] = array("style" => "red", "text" => "Email is already taken");

          if($key == "emailUnique"){
               $formErrorMessage .= "<li style='" . $DisplayErrorForm["emailUnique"]["style"] . "'>" . $DisplayErrorForm["emailUnique"]["text"] . "</li>";
             }
          }
       }

if(count($DisplayErrorForm)) {
  $errorField = "<div class=\"alert alert-danger\">".
                            "<strong>Whoops!</strong> There were some problems with your input.<br><br>".
                            "<ul>".$formErrorMessage."</ul>".
                        "</div>";
        }
        if (!$hasErrors) {
        //Do the database input

然后在你的html部分调用$ errorField

<div>
<?php echo $errorField; ?>
</div>

Answer 2

答案是绑定值并使用rowCount（）。它使用以下代码：

$emailcheck = $bdd->prepare('SELECT * FROM ' . DB_TABLE . ' WHERE email = ?');
$emailcheck->bindValue( 1, $_POST['email'] );
$emailcheck->execute();


if ($emailcheck->rowCount() > 0) {
    $_SESSION['err_msg']="e-mail addresse already registered";
    $erreur=true;
    $emailcheck->closeCursor();
    header ('Location: form.php');
}

查询而不是准备可能更容易..

检查表是否包含值不起作用（SELECT COUNT）

2 个答案: