PHP的filter\u var filter\u VALIDATE\u电子邮件真的有效吗？

在阅读了各种帖子之后，我决定不使用正则表达式来检查电子邮件是否有效，而只使用PHP内置的filter_var函数。它似乎工作正常，直到它开始告诉我一封电子邮件是无效的，因为我有一个号码在里面

即name@domain.com工作，而name2@domain.com没有

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是我遗漏了什么，还是过滤var$电子邮件、过滤验证电子邮件真的很无效？

name2@domain.com似乎效果不错：

但我确实看到人们抱怨它有问题，即使如此。很可能，它确实有问题，但正则表达式解决方案也会有问题。电子邮件地址规范非常非常复杂

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这就是为什么验证电子邮件的唯一方法是向该地址发送电子邮件，并要求采取措施，例如：如果是注册脚本，请他们单击验证链接。

该过滤器最近已改进。 -在代码板使用的版本中，您的案例已正确过滤

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你也可以看看和。Regexp非常可怕。

PHP5.3.3过滤代码中使用的正则表达式基于MichaelRushton的博客about。这似乎对你提到的案子有效

您还可以查看PHP中当前使用的regexp中的一些选项，这是经过测试的选项之一

然后您可以选择一个您更喜欢的regexp，并在调用preg_match时使用它

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或者您可以使用regexp并替换文件PHP/ext/filter/logical\u filter.c中的一个，使用函数PHP\u filter\u validate\u email，然后重建PHP。

谢谢。我将发送一封验证电子邮件。如果有什么东西可以确保人们不会意外地输入明显错误的字符，那就太好了。@Keen我不是说将正则表达式验证抛出窗外；你可以验证它，如果它失败，警告用户。例如：计算机说你的电子邮件无效，但它不是很聪明。您确定要使用此电子邮件吗？测试电子邮件地址中是否存在点也是必要的@威尔·丹斯芬：你的问题不准确。name2@domain.com在所有支持filter_var的PHP版本上都可以很好地工作。证明：Michael Rushton博客的链接现在为您带来了一个空页面：@Matteo，您可以在PHP源代码中找到相同的代码。或者在wayback机器中查找Michael Rushton的博客：

function isValidEmail($email, $checkDNS = false)
{

    $valid = (
            /* Preference for native version of function */
            function_exists('filter_var') and filter_var($email, FILTER_VALIDATE_EMAIL)
            ) || (
                /* The maximum length of an e-mail address is 320 octets, per RFC 2821. */
                strlen($email) <= 320
                /*
                 * The regex below is based on a regex by Michael Rushton.
                 * However, it is not identical. I changed it to only consider routeable
                 * addresses as valid. Michael's regex considers a@b a valid address
                 * which conflicts with section 2.3.5 of RFC 5321 which states that:
                 *
                 * Only resolvable, fully-qualified domain names (FQDNs) are permitted
                 * when domain names are used in SMTP. In other words, names that can
                 * be resolved to MX RRs or address (i.e., A or AAAA) RRs (as discussed
                 * in Section 5) are permitted, as are CNAME RRs whose targets can be
                 * resolved, in turn, to MX or address RRs. Local nicknames or
                 * unqualified names MUST NOT be used.
                 *
                 * This regex does not handle comments and folding whitespace. While
                 * this is technically valid in an email address, these parts aren't
                 * actually part of the address itself.
                 */
                and preg_match_all(
                    '/^(?!(?:(?:\\x22?\\x5C[\\x00-\\x7E]\\x22?)|(?:\\x22?[^\\x5C\\x22]\\x22?))'.
                    '{255,})(?!(?:(?:\\x22?\\x5C[\\x00-\\x7E]\\x22?)|(?:\\x22?[^\\x5C\\x22]\\x22?))'.
                    '{65,}@)(?:(?:[\\x21\\x23-\\x27\\x2A\\x2B\\x2D\\x2F-\\x39\\x3D\\x3F\\x5E-\\x7E]+)|'.
                    '(?:\\x22(?:[\\x01-\\x08\\x0B\\x0C\\x0E-\\x1F\\x21\\x23-\\x5B\\x5D-\\x7F]|(?:\\x5C[\\x00-\\x7F]))*\\x22))'.
                    '(?:\\.(?:(?:[\\x21\\x23-\\x27\\x2A\\x2B\\x2D\\x2F-\\x39\\x3D\\x3F\\x5E-\\x7E]+)|'.
                    '(?:\\x22(?:[\\x01-\\x08\\x0B\\x0C\\x0E-\\x1F\\x21\\x23-\\x5B\\x5D-\\x7F]|'.
                    '(?:\\x5C[\\x00-\\x7F]))*\\x22)))*@(?:(?:(?!.*[^.]{64,})'.
                    '(?:(?:(?:xn--)?[a-z0-9]+(?:-+[a-z0-9]+)*\\.){1,126})'.'{1,}'.
                    '(?:(?:[a-z][a-z0-9]*)|(?:(?:xn--)[a-z0-9]+))(?:-+[a-z0-9]+)*)|'.
                    '(?:\\[(?:(?:IPv6:(?:(?:[a-f0-9]{1,4}(?::[a-f0-9]{1,4}){7})|'.
                    '(?:(?!(?:.*[a-f0-9][:\\]]){7,})(?:[a-f0-9]{1,4}(?::[a-f0-9]{1,4}){0,5})?::'.
                    '(?:[a-f0-9]{1,4}(?::[a-f0-9]{1,4}){0,5})?)))|'.
                    '(?:(?:IPv6:(?:(?:[a-f0-9]{1,4}(?::[a-f0-9]{1,4}){5}:)|'.
                    '(?:(?!(?:.*[a-f0-9]:){5,})'.'(?:[a-f0-9]{1,4}(?::[a-f0-9]{1,4}){0,3})?::'.
                    '(?:[a-f0-9]{1,4}(?::[a-f0-9]{1,4}){0,3}:)?)))?(?:(?:25[0-5])|'.
                    '(?:2[0-4][0-9])|(?:1[0-9]{2})|(?:[1-9]?[0-9]))(?:\\.(?:(?:25[0-5])|'.
                    '(?:2[0-4][0-9])|(?:1[0-9]{2})|(?:[1-9]?[0-9]))){3}))\\]))$/iD',
                    $email)
            );

    if( $valid )
    {
        if( $checkDNS && ($domain = end(explode('@',$email, 2))) )
        {
            /*
            Note:
            Adding the dot enforces the root.
            The dot is sometimes necessary if you are searching for a fully qualified domain
            which has the same name as a host on your local domain.
            Of course the dot does not alter results that were OK anyway.
            */
            return checkdnsrr($domain . '.', 'MX');
        }
        return true;
    }
    return false;
}


//-----------------------------------------------------------------

    var_dump(isValidEmail('nechtan@tagon8inc.com', true));
    // bool(true)