wp-includes/formatting.php:3543Verifies that an email is valid.
$emailstring$deprecatedbooloptionalfalsestring|false9 hooks fire while is_email() runs, in this order:
Filters whether an email address is valid.
Filters whether an email address is valid.
Filters whether an email address is valid.
Filters whether an email address is valid.
Filters whether an email address is valid.
Filters whether an email address is valid.
Filters whether an email address is valid.
Filters whether an email address is valid.
Filters whether an email address is valid.
function is_email( $email, $deprecated = false ) { if ( ! empty( $deprecated ) ) { _deprecated_argument( __FUNCTION__, '3.0.0' ); } // Test for the minimum length the email can be. if ( strlen( $email ) < 6 ) { /** * Filters whether an email address is valid. * * This filter is evaluated under several different contexts, such as 'email_too_short', * 'email_no_at', 'local_invalid_chars', 'domain_period_sequence', 'domain_period_limits', * 'domain_no_periods', 'sub_hyphen_limits', 'sub_invalid_chars', or no specific context. * * @since 2.8.0 * * @param string|false $is_email The email address if successfully passed the is_email() checks, false otherwise. * @param string $email The email address being checked. * @param string $context Context under which the email was tested. */ return apply_filters( 'is_email', false, $email, 'email_too_short' ); } // Test for an @ character after the first position. if ( strpos( $email, '@', 1 ) === false ) { /** This filter is documented in wp-includes/formatting.php */ return apply_filters( 'is_email', false, $email, 'email_no_at' ); } // Split out the local and domain parts. list( $local, $domain ) = explode( '@', $email, 2 ); /* * LOCAL PART * Test for invalid characters. */ if ( ! preg_match( '/^[a-zA-Z0-9!#$%&\'*+\/=?^_`{|}~\.-]+$/', $local ) ) { /** This filter is documented in wp-includes/formatting.php */ return apply_filters( 'is_email', false, $email, 'local_invalid_chars' ); } /* * DOMAIN PART * Test for sequences of periods. */ if ( preg_match( '/\.{2,}/', $domain ) ) { /** This filter is documented in wp-includes/formatting.php */ return apply_filters( 'is_email', false, $email, 'domain_period_sequence' ); } // Test for leading and trailing periods and whitespace. if ( trim( $domain, " \t\n\r\0\x0B." ) !== $domain ) { /** This filter is documented in wp-includes/formatting.php */ return apply_filters( 'is_email', false, $email, 'domain_period_limits' ); } // Split the domain into subs. $subs = explode( '.', $domain ); // Assume the domain will have at least two subs. if ( 2 > count( $subs ) ) { /** This filter is documented in wp-includes/formatting.php */ return apply_filters( 'is_email', false, $email, 'domain_no_periods' ); } // Loop through each sub. foreach ( $subs as $sub ) { // Test for leading and trailing hyphens and whitespace. if ( trim( $sub, " \t\n\r\0\x0B-" ) !== $sub ) { /** This filter is documented in wp-includes/formatting.php */ return apply_filters( 'is_email', false, $email, 'sub_hyphen_limits' ); } // Test for invalid characters. if ( ! preg_match( '/^[a-z0-9-]+$/i', $sub ) ) { /** This filter is documented in wp-includes/formatting.php */ return apply_filters( 'is_email', false, $email, 'sub_invalid_chars' ); } }Introduced in 0.71. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/formatting.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.