PHP / MySQL会员系统总是给我电子邮件已经注册 - PHP/MySQL Member System always gives me Email Already Registered

PHP/MySQL Member System always gives me Email Already Registered

成员系统代码总是将我重定向到"电子邮件已注册页面"
这是我在处理时使用的代码，用于检查电子邮件是否为用户名
是否已被采取
请帮忙!!!

<?php
    $db_host = "localhost";
    $db_user = "ms_admin";
    $db_pass = "secretpassword";
    $db_name = "member_system";
     $connection = mysqli_connect($db_host, $db_user, $db_pass, $db_name);
    if(mysqli_connect_errno())
        die("Databse connection failed." . mysqli_connect_error()
            . " (" . mysqli_connect_errno() . ")" );
?>
<?php
    function check_email($e_mail)
    {
        $query  = "SELECT email FROM members ";
        $query .= "WHERE email='$e_mail'";
        $result = mysqli_query($connection, $query);
        $num_rows = mysqli_num_rows($result);
        if($num_rows>0) header("Location: registration_successful.php");
         else header("Location: registration_unsuccessful.php");
    }
?>
<?php
    $full_name = ucwords($_POST["full_name"]);
    $email = strtolower($_POST["email"]);
    $password = md5($_POST["password"]);
    check_email($email);
?>

我改变了那些：

 if($num_rows>0) header("Location: registration_successful.php");
  else header("Location: registration_unsuccessful.php");

自：

 if($num_rows>0) header("Location: registration_unsuccessful.php");
  else header("Location: registration_successful.php");

似乎（$num_rows>0）总是返回 FALSE :(

请帮忙，，谢谢。。。。

check_email（）中缺少$connection变量，请global $connection;像

function check_email($e_mail){
        global $connection;
        $query  = "SELECT email FROM members ";
        $query .= "WHERE email='$e_mail'";
        $result = mysqli_query($connection, $query);
        $num_rows = mysqli_num_rows($result);
        if($num_rows>0) header("Location: registration_successful.php");
         else header("Location: registration_unsuccessful.php");
     }

     check_email($email);

或

 function check_email($e_mail, $connection){
    $query  = "SELECT email FROM members ";
    $query .= "WHERE email='$e_mail'";
    $result = mysqli_query($connection, $query);
    $num_rows = mysqli_num_rows($result);
    if($num_rows>0) header("Location: registration_successful.php");
     else header("Location: registration_unsuccessful.php");
 }

 check_email($email, $connection);

虽然我喜欢第一:)

问题出在重定向用户之前的测试中：

// if the rows are > 0 then it means the email already exists 
// which means we should redirect to the unsuccessful registration page
if($num_rows>0) header("Location: registration_unsuccessful.php");
     else echo header("Location: registration_successful.php");
// else, we redirect to successful registration page (meaning the email does not exists in DB)

正如@Mihai提到的，您忘记连接查询字符串。

尝试以下代码

<?php
function check_email($e_mail)
{
    $query = "SELECT email FROM members";
    $query .= "WHERE email='$e_mail'";
    $result = mysqli_query($connection, $query);
    $num_rows = mysqli_num_rows($result);
    if($num_rows>0) header("Location: registration_unsuccessful.php");
     else echo header("Location: registration_successful.php")
}
?>
<?php
$full_name = ucwords($_POST["full_name"]);
$email = strtolower($_POST["email"]);
$password = md5($_POST["password"]);
check_email($email);
?>

使用

    $query  = "SELECT email FROM members ";
    $query .= "WHERE email='".$e_mail."'";

您错过了成员之后的空间，将其复制粘贴到您的代码中。

或使用简单的解决方案

    $query  = "SELECT email FROM members WHERE email='".$e_mail."'";

更新

mysqli_store_result($connection);
$num_rows= mysqli_num_rows($user_query);
if($num_rows>0)

原因 ->使用store_result缓冲结果。