while循环php中的最后一个元素

Question

$result = $conn->query("SELECT * FROM mails");
while($row = $result->fetch_assoc()){
    $mymail= $row['mail']. ",";
    echo $mymail;
}

我在每行逗号（，）后都有，但我不想在最后一行之后（，）。我怎么能这样做？

Answer 1

查看join功能：

$mails = array();
$result = $conn->query("SELECT * FROM mails");
while($row = $result->fetch_assoc())
{
    $mails[] = $row['mail']; // Store E-Mail adresses in an array
}
$commaSeparatedMails = join(',', $mails); // Connect all array parts using a comma
echo $commaSeparatedMails;

Answer 2

rtrim（yourstring，＆＃34;，＆＃34;），此函数将删除右逗号。