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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 |
|---|---|
| 1759 | * @param boolean $deprecated Deprecated. |
| 1760 | * @return string|bool Either false or the valid email address. |
| 1761 | */ |
| 1762 | function is_email( $email, $deprecated = false ) { |
| 1763 | if ( ! empty( $deprecated ) ) |
| 1764 | _deprecated_argument( __FUNCTION__, '3.0' ); |
| 1765 | |
| 1766 | // Test for the minimum length the email can be |
| 1767 | if ( strlen( $email ) < 3 ) { |
| 1768 | return apply_filters( 'is_email', false, $email, 'email_too_short' ); |
| 1769 | } |
| 1770 | |
| 1771 | // Test for an @ character after the first position |
| 1772 | if ( strpos( $email, '@', 1 ) === false ) { |
| 1773 | return apply_filters( 'is_email', false, $email, 'email_no_at' ); |
| 1774 | } |
| 1775 | |
| 1776 | // Split out the local and domain parts |
| 1777 | list( $local, $domain ) = explode( '@', $email, 2 ); |
| 1778 | |
| 1779 | // LOCAL PART |
| 1780 | // Test for invalid characters |
| 1781 | if ( !preg_match( '/^[a-zA-Z0-9!#$%&\'*+\/=?^_`{|}~\.-]+$/', $local ) ) { |
| 1782 | return apply_filters( 'is_email', false, $email, 'local_invalid_chars' ); |
| 1783 | } |
| 1784 | |
| 1785 | // DOMAIN PART |
| 1786 | // Test for sequences of periods |
| 1787 | if ( preg_match( '/\.{2,}/', $domain ) ) { |
| 1788 | return apply_filters( 'is_email', false, $email, 'domain_period_sequence' ); |
| 1789 | } |
| 1790 | |
| 1791 | // Test for leading and trailing periods and whitespace |
| 1792 | if ( trim( $domain, " \t\n\r\0\x0B." ) !== $domain ) { |
| 1793 | return apply_filters( 'is_email', false, $email, 'domain_period_limits' ); |
| 1794 | } |
| 1795 | |
| 1796 | // Split the domain into subs |
| 1797 | $subs = explode( '.', $domain ); |
| 1798 | |
| 1799 | // Assume the domain will have at least two subs |
| 1800 | if ( 2 > count( $subs ) ) { |
| 1801 | return apply_filters( 'is_email', false, $email, 'domain_no_periods' ); |
| 1802 | } |
| 1803 | |
| 1804 | // Loop through each sub |
| 1805 | foreach ( $subs as $sub ) { |
| 1806 | // Test for leading and trailing hyphens and whitespace |
| 1807 | if ( trim( $sub, " \t\n\r\0\x0B-" ) !== $sub ) { |
| 1808 | return apply_filters( 'is_email', false, $email, 'sub_hyphen_limits' ); |
| 1809 | } |
| 1810 | |
| 1811 | // Test for invalid characters |
| 1812 | if ( !preg_match('/^[a-z0-9-]+$/i', $sub ) ) { |
| 1813 | return apply_filters( 'is_email', false, $email, 'sub_invalid_chars' ); |
| 1814 | } |
| 1815 | } |
| 1816 | |
| 1817 | // Congratulations your email made it! |
| 1818 | return apply_filters( 'is_email', $email, $email, null ); |
| 1819 | } |
| 1820 | |
| 1821 | /** |
| 1822 | * Convert to ASCII from email subjects. |
| 1823 | * |
| 1824 | * @since 1.2.0 |
| 1825 | * @usedby wp_mail() handles charsets in email subjects |
| 1826 | * |
| 1827 | * @param string $string Subject line |