Question

我有一个表单可以在我的网站上注册电子邮件。我试图在PHP中创建一个检查，首先确定电子邮件是否已经在DB中注册，然后再允许用户再次注册。

IF声明没有执行....我做错了什么？ else语句工作正常。

请注意 - db.php文件包含连接设置$ conn。 else语句将电子邮件地址放入db。

＆＃13;

    <?php

include_once 'db.php';

$fullname = $_POST['signup_name_of_user'];
$email = $_POST['signup_email_of_user'];


mysqli_select_db('database');

if(isset($_POST['signup_email_of_user']))
{
  $checkdata = "SELECT signup_email_of_user FROM database WHERE signup_email_of_user = '$email'";
  $query = mysqli_query($conn, $checkdata);
  if(mysqli_num_rows($query>0))
  {
    echo "E-mail Already Exists. You cannot register more than twice!";
    exit();
      }

  else {
    $sql = "INSERT INTO database (signup_name_of_user, signup_email_of_user) VALUES ('$fullname', '$email')";

    mysqli_query($conn, $sql);

    echo "You have been successfully registered";


  }
}

 ?>

＆＃13;

Answer 1

您的PHP脚本中只有一个拼写错误，请更改

if(mysqli_num_rows($query>0))

向

if(mysqli_num_rows($query) > 0)

Answer 2

{{1}} 会这样做的！

PHP mySQL if语句 - 检查数据库中是否已有电子邮件

2 个答案: