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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 |
|---|---|
| 1785 | * @param boolean $deprecated Deprecated. |
| 1786 | * @return string|bool Either false or the valid email address. |
| 1787 | */ |
| 1788 | function is_email( $email, $deprecated = false ) { |
| 1789 | if ( ! empty( $deprecated ) ) |
| 1790 | _deprecated_argument( __FUNCTION__, '3.0' ); |
| 1791 | |
| 1792 | // Test for the minimum length the email can be |
| 1793 | if ( strlen( $email ) < 3 ) { |
| 1794 | return apply_filters( 'is_email', false, $email, 'email_too_short' ); |
| 1795 | } |
| 1796 | |
| 1797 | // Test for an @ character after the first position |
| 1798 | if ( strpos( $email, '@', 1 ) === false ) { |
| 1799 | return apply_filters( 'is_email', false, $email, 'email_no_at' ); |
| 1800 | } |
| 1801 | |
| 1802 | // Split out the local and domain parts |
| 1803 | list( $local, $domain ) = explode( '@', $email, 2 ); |
| 1804 | |
| 1805 | // LOCAL PART |
| 1806 | // Test for invalid characters |
| 1807 | if ( !preg_match( '/^[a-zA-Z0-9!#$%&\'*+\/=?^_`{|}~\.-]+$/', $local ) ) { |
| 1808 | return apply_filters( 'is_email', false, $email, 'local_invalid_chars' ); |
| 1809 | } |
| 1810 | |
| 1811 | // DOMAIN PART |
| 1812 | // Test for sequences of periods |
| 1813 | if ( preg_match( '/\.{2,}/', $domain ) ) { |
| 1814 | return apply_filters( 'is_email', false, $email, 'domain_period_sequence' ); |
| 1815 | } |
| 1816 | |
| 1817 | // Test for leading and trailing periods and whitespace |
| 1818 | if ( trim( $domain, " \t\n\r\0\x0B." ) !== $domain ) { |
| 1819 | return apply_filters( 'is_email', false, $email, 'domain_period_limits' ); |
| 1820 | } |
| 1821 | |
| 1822 | // Split the domain into subs |
| 1823 | $subs = explode( '.', $domain ); |
| 1824 | |
| 1825 | // Assume the domain will have at least two subs |
| 1826 | if ( 2 > count( $subs ) ) { |
| 1827 | return apply_filters( 'is_email', false, $email, 'domain_no_periods' ); |
| 1828 | } |
| 1829 | |
| 1830 | // Loop through each sub |
| 1831 | foreach ( $subs as $sub ) { |
| 1832 | // Test for leading and trailing hyphens and whitespace |
| 1833 | if ( trim( $sub, " \t\n\r\0\x0B-" ) !== $sub ) { |
| 1834 | return apply_filters( 'is_email', false, $email, 'sub_hyphen_limits' ); |
| 1835 | } |
| 1836 | |
| 1837 | // Test for invalid characters |
| 1838 | if ( !preg_match('/^[a-z0-9-]+$/i', $sub ) ) { |
| 1839 | return apply_filters( 'is_email', false, $email, 'sub_invalid_chars' ); |
| 1840 | } |
| 1841 | } |
| 1842 | |
| 1843 | // Congratulations your email made it! |
| 1844 | return apply_filters( 'is_email', $email, $email, null ); |
| 1845 | } |
| 1846 | |
| 1847 | /** |
| 1848 | * Convert to ASCII from email subjects. |
| 1849 | * |
| 1850 | * @since 1.2.0 |
| 1851 | * |
| 1852 | * @param string $string Subject line |
| 1853 | * @return string Converted string to ASCII |