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do_action( "hook_name" )
apply_filters( "hook_name", "what_to_filter" )
.Remember, this hook may occur in more than one file. Moreover, the hook's context may change from version to version.
This hook occurs 9 times in this file.
Line | Code |
---|---|
1493 | * @param boolean $deprecated Deprecated. |
1494 | * @return string|bool Either false or the valid email address. |
1495 | */ |
1496 | function is_email( $email, $deprecated = false ) { |
1497 | if ( ! empty( $deprecated ) ) |
1498 | _deprecated_argument( __FUNCTION__, '3.0' ); |
1499 |
|
1500 | // Test for the minimum length the email can be |
1501 | if ( strlen( $email ) < 3 ) { |
1502 | return apply_filters( 'is_email', false, $email, 'email_too_short' ); |
1503 | } |
1504 |
|
1505 | // Test for an @ character after the first position |
1506 | if ( strpos( $email, '@', 1 ) === false ) { |
1507 | return apply_filters( 'is_email', false, $email, 'email_no_at' ); |
1508 | } |
1509 |
|
1510 | // Split out the local and domain parts |
1511 | list( $local, $domain ) = explode( '@', $email, 2 ); |
1512 |
|
1513 | // LOCAL PART |
1514 | // Test for invalid characters |
1515 | if ( !preg_match( '/^[a-zA-Z0-9!#$%&\'*+\/=?^_`{|}~\.-]+$/', $local ) ) { |
1516 | return apply_filters( 'is_email', false, $email, 'local_invalid_chars' ); |
1517 | } |
1518 |
|
1519 | // DOMAIN PART |
1520 | // Test for sequences of periods |
1521 | if ( preg_match( '/\.{2,}/', $domain ) ) { |
1522 | return apply_filters( 'is_email', false, $email, 'domain_period_sequence' ); |
1523 | } |
1524 |
|
1525 | // Test for leading and trailing periods and whitespace |
1526 | if ( trim( $domain, " \t\n\r\0\x0B." ) !== $domain ) { |
1527 | return apply_filters( 'is_email', false, $email, 'domain_period_limits' ); |
1528 | } |
1529 |
|
1530 | // Split the domain into subs |
1531 | $subs = explode( '.', $domain ); |
1532 |
|
1533 | // Assume the domain will have at least two subs |
1534 | if ( 2 > count( $subs ) ) { |
1535 | return apply_filters( 'is_email', false, $email, 'domain_no_periods' ); |
1536 | } |
1537 |
|
1538 | // Loop through each sub |
1539 | foreach ( $subs as $sub ) { |
1540 | // Test for leading and trailing hyphens and whitespace |
1541 | if ( trim( $sub, " \t\n\r\0\x0B-" ) !== $sub ) { |
1542 | return apply_filters( 'is_email', false, $email, 'sub_hyphen_limits' ); |
1543 | } |
1544 |
|
1545 | // Test for invalid characters |
1546 | if ( !preg_match('/^[a-z0-9-]+$/i', $sub ) ) { |
1547 | return apply_filters( 'is_email', false, $email, 'sub_invalid_chars' ); |
1548 | } |
1549 | } |
1550 |
|
1551 | // Congratulations your email made it! |
1552 | return apply_filters( 'is_email', $email, $email, null ); |
1553 | } |
1554 |
|
1555 | /** |
1556 | * Convert to ASCII from email subjects. |
1557 | * |
1558 | * @since 1.2.0 |
1559 | * @usedby wp_mail() handles charsets in email subjects |
1560 | * |
1561 | * @param string $string Subject line |