在FILTER_VALIDATE_EMAIL中有一个更好的正则表达式，但任何正则表达式都可能给出糟糕的结果。

例如. .

// "not an email" is invalid so its false.
php > var_export(filter_var("not an email", FILTER_VALIDATE_EMAIL));
false
// "foo@a.com" looks like an email, so it passes even though its not real.
php > var_export(filter_var("foo@a.com", FILTER_VALIDATE_EMAIL));
'foo@a.com'
// "foo@gmail.com" passes, gmail is a valid email server,
//  but gmail require more than 3 letters for the address.
var_export(filter_var("foo@gmail.com", FILTER_VALIDATE_EMAIL));
'foo@gmail.com'

你可能会考虑使用像Real Email这样的API，它可以进行深入的邮箱检查，以检查电子邮件是否真实。

有点像…

$email = "foo@bar.com";
$api_key = ???;

$request_context = stream_context_create(array(
    'http' => array(
        'header'  => "Authorization: Bearer " . $api_key
    )
));

$result_json = file_get_contents("https://isitarealemail.com/api/email/validate?email=" . $email, false, $request_context);

if (json_decode($result_json, true)['status'] == "valid") {
    echo("email is valid");
} else if (json_decode($result_json, true)['status'] == "invalid") {
    echo("email is invalid");
} else {
  echo("email was unknown");
}

您可以为此使用filter_var。

<?php
   function validateEmail($email) {
      return filter_var($email, FILTER_VALIDATE_EMAIL);
   }
?>

在FILTER_VALIDATE_EMAIL中有一个更好的正则表达式，但任何正则表达式都可能给出糟糕的结果。

例如. .

// "not an email" is invalid so its false.
php > var_export(filter_var("not an email", FILTER_VALIDATE_EMAIL));
false
// "foo@a.com" looks like an email, so it passes even though its not real.
php > var_export(filter_var("foo@a.com", FILTER_VALIDATE_EMAIL));
'foo@a.com'
// "foo@gmail.com" passes, gmail is a valid email server,
//  but gmail require more than 3 letters for the address.
var_export(filter_var("foo@gmail.com", FILTER_VALIDATE_EMAIL));
'foo@gmail.com'

你可能会考虑使用像Real Email这样的API，它可以进行深入的邮箱检查，以检查电子邮件是否真实。

有点像…

$email = "foo@bar.com";
$api_key = ???;

$request_context = stream_context_create(array(
    'http' => array(
        'header'  => "Authorization: Bearer " . $api_key
    )
));

$result_json = file_get_contents("https://isitarealemail.com/api/email/validate?email=" . $email, false, $request_context);

if (json_decode($result_json, true)['status'] == "valid") {
    echo("email is valid");
} else if (json_decode($result_json, true)['status'] == "invalid") {
    echo("email is invalid");
} else {
  echo("email was unknown");
}

我认为你最好使用PHP的内置过滤器-在这种特殊情况下:

当提供FILTER_VALIDATE_EMAIL参数时，它可以返回true或false。

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");
}

/(?![[:alnum:]]|@|-|_|\.)./

现在，如果你使用带有type=email的HTML5表单，那么你已经有80%的安全性了，因为浏览器引擎有它们自己的验证器。为了补充它，将这个正则表达式添加到你的preg_match_all()并对其求反:

if (!preg_match_all("/(?![[:alnum:]]|@|-|_|\.)./",$email)) { .. }

找到HTML5表单使用的正则表达式进行验证 https://regex101.com/r/mPEKmy/1