我有这个功能来验证一个电子邮件地址:
function validateEMAIL($EMAIL) {
$v = "/[a-zA-Z0-9_-.+]+@[a-zA-Z0-9-]+.[a-zA-Z]+/";
return (bool)preg_match($v, $EMAIL);
}
这样可以检查电子邮件地址是否有效吗?
当前回答
根据我的经验，regex解决方案有太多的假阳性，而filter_var()解决方案有假阴性(特别是对于所有新的tld)。
相反，最好是确保地址具有电子邮件地址的所有必需部分(用户、“@”符号和域)，然后验证域本身是否存在。
无法确定(服务器端)外部域是否存在电子邮件用户。
这是我在Utility类中创建的一个方法:
public static function validateEmail(string $email): bool {
// SET INITIAL RETURN VARIABLE
// ENSURE -> EMAIL ISN'T EMPTY | AN @ SYMBOL IS PRESENT
$emailIsValid = FALSE;
if (
!empty($email) &&
strpos($email, '@') !== FALSE
) {
// GET EMAIL PARTS
$email = explode('@', $email);
$user = $email[0];
$domain = $email[1];
// VALIDATE EMAIL ADDRESS
if (
count($email) === 2 &&
!empty($user) &&
!empty($domain) &&
checkdnsrr($domain)
) {
$emailIsValid = TRUE;
}
}
// RETURN RESULT
return $emailIsValid;
}
其他回答
使用以下代码:
// Variable to check
$email = "john.doe@example.com";
// Remove all illegal characters from email
$email = filter_var($email, FILTER_SANITIZE_EMAIL);
// Validate e-mail
if (filter_var($email, FILTER_VALIDATE_EMAIL)) {
echo("Email is a valid email address");
}
根据我的经验，regex解决方案有太多的假阳性，而filter_var()解决方案有假阴性(特别是对于所有新的tld)。
相反，最好是确保地址具有电子邮件地址的所有必需部分(用户、“@”符号和域)，然后验证域本身是否存在。
无法确定(服务器端)外部域是否存在电子邮件用户。
这是我在Utility类中创建的一个方法:
public static function validateEmail(string $email): bool {
// SET INITIAL RETURN VARIABLE
// ENSURE -> EMAIL ISN'T EMPTY | AN @ SYMBOL IS PRESENT
$emailIsValid = FALSE;
if (
!empty($email) &&
strpos($email, '@') !== FALSE
) {
// GET EMAIL PARTS
$email = explode('@', $email);
$user = $email[0];
$domain = $email[1];
// VALIDATE EMAIL ADDRESS
if (
count($email) === 2 &&
!empty($user) &&
!empty($domain) &&
checkdnsrr($domain)
) {
$emailIsValid = TRUE;
}
}
// RETURN RESULT
return $emailIsValid;
}
如果你只是在寻找一个实际的正则表达式，允许各种点，下划线和破折号，它如下:[a-zA-z0-9.-]+\@[a-zA-z0-9.-]+.[a-zA-Z]+。这将允许像tom_anderson.1-neo@my-mail_matrix.com这样看起来相当愚蠢的电子邮件被验证。
这不仅可以验证你的邮件，还可以过滤掉意想不到的字符:
$email = $_POST['email'];
$emailB = filter_var($email, FILTER_SANITIZE_EMAIL);
if (filter_var($emailB, FILTER_VALIDATE_EMAIL) === false ||
$emailB != $email
) {
echo "This email adress isn't valid!";
exit(0);
}
在关于电子邮件验证的“顶级问题”中回答了这个问题https://stackoverflow.com/a/41129750/1848217
For me the right way for checking emails is: Check that symbol @ exists, and before and after it there are some non-@ symbols: /^[^@]+@[^@]+$/ Try to send an email to this address with some "activation code". When the user "activated" his email address, we will see that all is right. Of course, you can show some warning or tooltip in front-end when user typed "strange" email to help him to avoid common mistakes, like no dot in domain part or spaces in name without quoting and so on. But you must accept the address "hello@world" if user really want it. Also, you must remember that email address standard was and can evolute, so you can't just type some "standard-valid" regexp once and for all times. And you must remember that some concrete internet servers can fail some details of common standard and in fact work with own "modified standard".
所以，只要检查@，提示用户在前端和发送验证电子邮件在给定的地址。
