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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 |
|---|---|
| 1812 | * @param boolean $deprecated Deprecated. |
| 1813 | * @return string|bool Either false or the valid email address. |
| 1814 | */ |
| 1815 | function is_email( $email, $deprecated = false ) { |
| 1816 | if ( ! empty( $deprecated ) ) |
| 1817 | _deprecated_argument( __FUNCTION__, '3.0' ); |
| 1818 | |
| 1819 | // Test for the minimum length the email can be |
| 1820 | if ( strlen( $email ) < 3 ) { |
| 1821 | return apply_filters( 'is_email', false, $email, 'email_too_short' ); |
| 1822 | } |
| 1823 | |
| 1824 | // Test for an @ character after the first position |
| 1825 | if ( strpos( $email, '@', 1 ) === false ) { |
| 1826 | return apply_filters( 'is_email', false, $email, 'email_no_at' ); |
| 1827 | } |
| 1828 | |
| 1829 | // Split out the local and domain parts |
| 1830 | list( $local, $domain ) = explode( '@', $email, 2 ); |
| 1831 | |
| 1832 | // LOCAL PART |
| 1833 | // Test for invalid characters |
| 1834 | if ( !preg_match( '/^[a-zA-Z0-9!#$%&\'*+\/=?^_`{|}~\.-]+$/', $local ) ) { |
| 1835 | return apply_filters( 'is_email', false, $email, 'local_invalid_chars' ); |
| 1836 | } |
| 1837 | |
| 1838 | // DOMAIN PART |
| 1839 | // Test for sequences of periods |
| 1840 | if ( preg_match( '/\.{2,}/', $domain ) ) { |
| 1841 | return apply_filters( 'is_email', false, $email, 'domain_period_sequence' ); |
| 1842 | } |
| 1843 | |
| 1844 | // Test for leading and trailing periods and whitespace |
| 1845 | if ( trim( $domain, " \t\n\r\0\x0B." ) !== $domain ) { |
| 1846 | return apply_filters( 'is_email', false, $email, 'domain_period_limits' ); |
| 1847 | } |
| 1848 | |
| 1849 | // Split the domain into subs |
| 1850 | $subs = explode( '.', $domain ); |
| 1851 | |
| 1852 | // Assume the domain will have at least two subs |
| 1853 | if ( 2 > count( $subs ) ) { |
| 1854 | return apply_filters( 'is_email', false, $email, 'domain_no_periods' ); |
| 1855 | } |
| 1856 | |
| 1857 | // Loop through each sub |
| 1858 | foreach ( $subs as $sub ) { |
| 1859 | // Test for leading and trailing hyphens and whitespace |
| 1860 | if ( trim( $sub, " \t\n\r\0\x0B-" ) !== $sub ) { |
| 1861 | return apply_filters( 'is_email', false, $email, 'sub_hyphen_limits' ); |
| 1862 | } |
| 1863 | |
| 1864 | // Test for invalid characters |
| 1865 | if ( !preg_match('/^[a-z0-9-]+$/i', $sub ) ) { |
| 1866 | return apply_filters( 'is_email', false, $email, 'sub_invalid_chars' ); |
| 1867 | } |
| 1868 | } |
| 1869 | |
| 1870 | // Congratulations your email made it! |
| 1871 | return apply_filters( 'is_email', $email, $email, null ); |
| 1872 | } |
| 1873 | |
| 1874 | /** |
| 1875 | * Convert to ASCII from email subjects. |
| 1876 | * |
| 1877 | * @since 1.2.0 |
| 1878 | * |
| 1879 | * @param string $string Subject line |
| 1880 | * @return string Converted string to ASCII |