从php中获取数据库中的电子邮件列表[复制]

This question already has an answer here:

Can Anyone help me with this

SELECT userEmail FROM users in mysql gets a email list like
userEmail
a@gmail.com
b@gmail.com

Currently $userEmail gets first email from the list
a@gmail.com
I am trying to get email list from database like
a@gmail.com,b@gmail.com

    <?php

    $mailselect = "SELECT userEmail FROM users";
    $mailselect2 = mysqli_query($mysqli, $mailselect) or die('-31' . mysqli_error());
    $recipients = mysqli_fetch_assoc($mailselect2);
    $userEmail = $recipients['userEmail'];    
   $recipientss = array(',', $row['recipients'] );    
    $to = 's.gurudharsan@gmail.com';
    $subject = "E-mail subject";
    $message = 'Testing1: ' . $userEmail . "
" .
               'Testing2: ' .  implode(',', $recipientss);
    $headers = 'From: s.gurudharsan@gmail.com' . "
" ;
    $headers .= 'Reply-To: s.gurudharsan@gmail.com' . "
";

    mail($to, $subject, $message, $headers);

    ?>

Currently mail() function sends this email Testing1: a@gmail.com Testing1:

implode(',', $recipientss); This code might be a problem. Anyone with some sugestion

Thanks Guys.

</div>

http://php.net/manual/en/mysqli-result.fetch-assoc.php

Fetch a result row as an associative array

Usage for multiple rows:

$emails = [];
while ($row = mysqli_fetch_assoc($mailselect2)) {
    $emails[]=$row['userEmail'];
}

Then $emails is an array filled with the email addresses, you can implode it.

most simple way is to use mysqli_fetch_all() function is place of mysqli_fetch_assoc(). You will get an array as a result

http://php.net/manual/en/mysqli-result.fetch-all.php