如何生成有效的长电子邮件地址？

Question

我的意思是：

$ php -r 'var_dump(filter_var(str_repeat("a", 64) . "@gmail.com", FILTER_VALIDATE_EMAIL));'
Command line code:1:
string(74) "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa@gmail.com"
$ php -r 'var_dump(filter_var(str_repeat("a", 65) . "@gmail.com", FILTER_VALIDATE_EMAIL));'
Command line code:1:
bool(false)

邮箱名的长度有限制吗？我需要一封长度超过 255 个字符的电子邮件（用于测试）。

UPD 让我解释一下我需要这个的目的。我想在我的测试中确保用户不能指定超过 255 个字符的电子邮件地址。这就是为什么我需要一个很长的电子邮件地址。

UPD 遵循 Justinas 的建议：

$ php -r 'var_dump(filter_var(str_repeat("a", 64) . "@" . str_repeat("g", 63) . ".com", FILTER_VALIDATE_EMAIL));'
Command line code:1:
string(132) "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa@ggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg.com"
$ php -r 'var_dump(filter_var(str_repeat("a", 64) . "@" . str_repeat("g", 64) . ".com", FILTER_VALIDATE_EMAIL));'
Command line code:1:
bool(false)

Answer 1

Source

The format of email addresses is local-part@domain where the local part may be up to 64 characters long and the domain may have a maximum of 255 characters

要生成一些长字符串，您可以使用像 str_repeat

这样简单的东西

var_dump(str_repeat('a', 64).'@'.str_repeat('g', 255).'.com');

Answer 2

You may use this Function to generate random email addresses conforming to a maximum of 64 characters Local-Part and a maximum of 255 characters Domain Part.

     <?php

        function generateEmailAddress($maxLenLocal=64, $maxLenDomain=255){
            $numeric        =  '0123456789';
            $alphabetic     = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
            $extras         = '.-_';
            $all            = $numeric . $alphabetic . $extras;
            $alphaNumeric   = $alphabetic . $numeric;
            $alphaNumericP  = $alphabetic . $numeric . "-";
            $randomString   = '';

            // GENERATE 1ST 4 CHARACTERS OF THE LOCAL-PART
            for ($i = 0; $i < 4; $i++) {
                $randomString .= $alphabetic[rand(0, strlen($alphabetic) - 1)];
            }
            // GENERATE A NUMBER BETWEEN 20 & 60
            $rndNum         = rand(20, $maxLenLocal-4);

            for ($i = 0; $i < $rndNum; $i++) {
                $randomString .= $all[rand(0, strlen($all) - 1)];
            }

            // ADD AN @ SYMBOL...
            $randomString .= "@";

            // GENERATE DOMAIN NAME - INITIAL 3 CHARS:
            for ($i = 0; $i < 3; $i++) {
                $randomString .= $alphabetic[rand(0, strlen($alphabetic) - 1)];
            }

            // GENERATE A NUMBER BETWEEN 15 & $maxLenDomain-7
            $rndNum2        = rand(15, $maxLenDomain-7);
            for ($i = 0; $i < $rndNum2; $i++) {
                $randomString .= $all[rand(0, strlen($all) - 1)];
            }
            // ADD AN DOT . SYMBOL...
            $randomString .= ".";

            // GENERATE TLD: 4
            for ($i = 0; $i < 4; $i++) {
                $randomString .= $alphaNumeric[rand(0, strlen($alphaNumeric) - 1)];
            }

            return $randomString;

        }


        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());
        var_dump(generateEmailAddress());

Answer 3

引用 the link Justinas 提供的更多内容：

The format of email addresses is local-part@domain where the local part may be up to 64 characters long and the domain may have a maximum of 255 characters—but the maximum of 256-character length of a forward or reverse path restricts the entire email address to be no more than 254 characters long.

现在，如果我们查看 filter_var 的 source，我们会发现那里基本上有两个检查：

如果整个电子邮件地址是 longer than 320 symbols
如果匹配the regex（除非我们指定FILTER_FLAG_EMAIL_UNICODE标志）

正则表达式可以改写如下：

/^
  ### check if total length is no more than 254 symbols
  (?!
    (?:
      (?:\x22?\x5C[\x00-\x7E]\x22?)
      |
      (?:\x22?[^\x5C\x22]\x22?)
    ){255,}
  )
  ### check if the part before @ is no more than 64 symbols
  (?!
    (?:
      (?:\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
      )
    )
  )*
  @
  (?:
    (?:
      ### no segment must be longer than 64 symbols
      (?!.*[^.]{64,})
      (?:
        (?:
          (?:xn--)?
          [a-z0-9]+
          (?:-+[a-z0-9]+)*
          \.
        ){1,126}
      ){1,}
      (?:
        (?:[a-z][a-z0-9]*)
        |
        (?:(?:xn--)[a-z0-9]+)
      )
      (?:-+[a-z0-9]+)*
    )
    |
    ### ip
    (?:
      \[
      (?:
        (?:
          IPv6:
          (?:
            (?:[a-f0-9]{1,4}(?::[a-f0-9]{1,4}){7})
            |
            (?:
              (?!(?:.*[a-f0-9][:\]]){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

知道我们能得到的最好的是：

$ php -r 'var_dump(filter_var(str_repeat("a", 64) . "@" . str_repeat(str_repeat("g", 63) . ".", 2) . str_repeat("g", 61), FILTER_VALIDATE_EMAIL));'
Command line code:1:
string(254) "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa@ggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg.ggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg.ggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg"
$ php -r 'var_dump(filter_var(str_repeat("a", 64) . "@" . str_repeat(str_repeat("g", 63) . ".", 2) . str_repeat("g", 62), FILTER_VALIDATE_EMAIL));'
Command line code:1:
bool(false)

如何生成有效的长电子邮件地址？

How do I generate long valid email address?

php

email

validation

email-address

rfc822