/** * WP_Theme Class * * @package WordPress * @subpackage Theme */ final class WP_Theme implements ArrayAccess { /** * Headers for style.css files. * * @static * @access private * @var array */ private static $file_headers = array( 'Name' => 'Theme Name', 'ThemeURI' => 'Theme URI', 'Description' => 'Description', 'Author' => 'Author', 'AuthorURI' => 'Author URI', 'Version' => 'Version', 'Template' => 'Template', 'Status' => 'Status', 'Tags' => 'Tags', 'TextDomain' => 'Text Domain', 'DomainPath' => 'Domain Path', ); /** * Default themes. * * @static * @access private * @var array */ private static $default_themes = array( 'classic' => 'WordPress Classic', 'default' => 'WordPress Default', 'twentyten' => 'Twenty Ten', 'twentyeleven' => 'Twenty Eleven', 'twentytwelve' => 'Twenty Twelve', 'twentythirteen' => 'Twenty Thirteen', 'twentyfourteen' => 'Twenty Fourteen', 'twentyfifteen' => 'Twenty Fifteen', ); /** * Renamed theme tags. * * @static * @access private * @var array */ private static $tag_map = array( 'fixed-width' => 'fixed-layout', 'flexible-width' => 'fluid-layout', ); /** * Absolute path to the theme root, usually wp-content/themes * * @access private * @var string */ private $theme_root; /** * Header data from the theme's style.css file. * * @access private * @var array */ private $headers = array(); /** * Header data from the theme's style.css file after being sanitized. * * @access private * @var array */ private $headers_sanitized; /** * Header name from the theme's style.css after being translated. * * Cached due to sorting functions running over the translated name. * * @access private * @var string */ private $name_translated; /** * Errors encountered when initializing the theme. * * @access private * @var WP_Error */ private $errors; /** * The directory name of the theme's files, inside the theme root. * * In the case of a child theme, this is directory name of the child theme. * Otherwise, 'stylesheet' is the same as 'template'. * * @access private * @var string */ private $stylesheet; /** * The directory name of the theme's files, inside the theme root. * * In the case of a child theme, this is the directory name of the parent theme. * Otherwise, 'template' is the same as 'stylesheet'. * * @access private * @var string */ private $template; /** * A reference to the parent theme, in the case of a child theme. * * @access private * @var WP_Theme */ private $parent; /** * URL to the theme root, usually an absolute URL to wp-content/themes * * @access private * var string */ private $theme_root_uri; /** * Flag for whether the theme's textdomain is loaded. * * @access private * @var bool */ private $textdomain_loaded; /** * Stores an md5 hash of the theme root, to function as the cache key. * * @access private * @var string */ private $cache_hash; /** * Flag for whether the themes cache bucket should be persistently cached. * * Default is false. Can be set with the wp_cache_themes_persistently filter. * * @static * @access private * @var bool */ private static $persistently_cache; /** * Expiration time for the themes cache bucket. * * By default the bucket is not cached, so this value is useless. * * @static * @access private * @var bool */ private static $cache_expiration = 1800; /** * Constructor for WP_Theme. * * @global array $wp_theme_directories * * @param string $theme_dir Directory of the theme within the theme_root. * @param string $theme_root Theme root. * @param WP_Error|void $_child If this theme is a parent theme, the child may be passed for validation purposes. */ public function __construct( $theme_dir, $theme_root, $_child = null ) { global $wp_theme_directories; // Initialize caching on first run. if ( ! isset( self::$persistently_cache ) ) { /** This action is documented in wp-includes/theme.php */ self::$persistently_cache = apply_filters( 'wp_cache_themes_persistently', false, 'WP_Theme' ); if ( self::$persistently_cache ) { wp_cache_add_global_groups( 'themes' ); if ( is_int( self::$persistently_cache ) ) self::$cache_expiration = self::$persistently_cache; } else { wp_cache_add_non_persistent_groups( 'themes' ); } } $this->theme_root = $theme_root; $this->stylesheet = $theme_dir; // Correct a situation where the theme is 'some-directory/some-theme' but 'some-directory' was passed in as part of the theme root instead. if ( ! in_array( $theme_root, (array) $wp_theme_directories ) && in_array( dirname( $theme_root ), (array) $wp_theme_directories ) ) { $this->stylesheet = basename( $this->theme_root ) . '/' . $this->stylesheet; $this->theme_root = dirname( $theme_root ); } $this->cache_hash = md5( $this->theme_root . '/' . $this->stylesheet ); $theme_file = $this->stylesheet . '/style.css'; $cache = $this->cache_get( 'theme' ); if ( is_array( $cache ) ) { foreach ( array( 'errors', 'headers', 'template' ) as $key ) { if ( isset( $cache[ $key ] ) ) $this->$key = $cache[ $key ]; } if ( $this->errors ) return; if ( isset( $cache['theme_root_template'] ) ) $theme_root_template = $cache['theme_root_template']; } elseif ( ! file_exists( $this->theme_root . '/' . $theme_file ) ) { $this->headers['Name'] = $this->stylesheet; if ( ! file_exists( $this->theme_root . '/' . $this->stylesheet ) ) $this->errors = new WP_Error( 'theme_not_found', sprintf( __( 'The theme directory "%s" does not exist.' ), esc_html( $this->stylesheet ) ) ); else $this->errors = new WP_Error( 'theme_no_stylesheet', __( 'Stylesheet is missing.' ) ); $this->template = $this->stylesheet; $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); if ( ! file_exists( $this->theme_root ) ) // Don't cache this one. $this->errors->add( 'theme_root_missing', __( 'ERROR: The themes directory is either empty or doesn’t exist. Please check your installation.' ) ); return; } elseif ( ! is_readable( $this->theme_root . '/' . $theme_file ) ) { $this->headers['Name'] = $this->stylesheet; $this->errors = new WP_Error( 'theme_stylesheet_not_readable', __( 'Stylesheet is not readable.' ) ); $this->template = $this->stylesheet; $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); return; } else { $this->headers = get_file_data( $this->theme_root . '/' . $theme_file, self::$file_headers, 'theme' ); // Default themes always trump their pretenders. // Properly identify default themes that are inside a directory within wp-content/themes. if ( $default_theme_slug = array_search( $this->headers['Name'], self::$default_themes ) ) { if ( basename( $this->stylesheet ) != $default_theme_slug ) $this->headers['Name'] .= '/' . $this->stylesheet; } } // (If template is set from cache [and there are no errors], we know it's good.) if ( ! $this->template && ! ( $this->template = $this->headers['Template'] ) ) { $this->template = $this->stylesheet; if ( ! file_exists( $this->theme_root . '/' . $this->stylesheet . '/index.php' ) ) { $this->errors = new WP_Error( 'theme_no_index', __( 'Template is missing.' ) ); $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); return; } } // If we got our data from cache, we can assume that 'template' is pointing to the right place. if ( ! is_array( $cache ) && $this->template != $this->stylesheet && ! file_exists( $this->theme_root . '/' . $this->template . '/index.php' ) ) { // If we're in a directory of themes inside /themes, look for the parent nearby. // wp-content/themes/directory-of-themes/* $parent_dir = dirname( $this->stylesheet ); if ( '.' != $parent_dir && file_exists( $this->theme_root . '/' . $parent_dir . '/' . $this->template . '/index.php' ) ) { $this->template = $parent_dir . '/' . $this->template; } elseif ( ( $directories = search_theme_directories() ) && isset( $directories[ $this->template ] ) ) { // Look for the template in the search_theme_directories() results, in case it is in another theme root. // We don't look into directories of themes, just the theme root. $theme_root_template = $directories[ $this->template ]['theme_root']; } else { // Parent theme is missing. $this->errors = new WP_Error( 'theme_no_parent', sprintf( __( 'The parent theme is missing. Please install the "%s" parent theme.' ), esc_html( $this->template ) ) ); $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); $this->parent = new WP_Theme( $this->template, $this->theme_root, $this ); return; } } // Set the parent, if we're a child theme. if ( $this->template != $this->stylesheet ) { // If we are a parent, then there is a problem. Only two generations allowed! Cancel things out. if ( $_child instanceof WP_Theme && $_child->template == $this->stylesheet ) { $_child->parent = null; $_child->errors = new WP_Error( 'theme_parent_invalid', sprintf( __( 'The "%s" theme is not a valid parent theme.' ), esc_html( $_child->template ) ) ); $_child->cache_add( 'theme', array( 'headers' => $_child->headers, 'errors' => $_child->errors, 'stylesheet' => $_child->stylesheet, 'template' => $_child->template ) ); // The two themes actually reference each other with the Template header. if ( $_child->stylesheet == $this->template ) { $this->errors = new WP_Error( 'theme_parent_invalid', sprintf( __( 'The "%s" theme is not a valid parent theme.' ), esc_html( $this->template ) ) ); $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); } return; } // Set the parent. Pass the current instance so we can do the crazy checks above and assess errors. $this->parent = new WP_Theme( $this->template, isset( $theme_root_template ) ? $theme_root_template : $this->theme_root, $this ); } // We're good. If we didn't retrieve from cache, set it. if ( ! is_array( $cache ) ) { $cache = array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ); // If the parent theme is in another root, we'll want to cache this. Avoids an entire branch of filesystem calls above. if ( isset( $theme_root_template ) ) $cache['theme_root_template'] = $theme_root_template; $this->cache_add( 'theme', $cache ); } } /** * When converting the object to a string, the theme name is returned. * * @return string Theme name, ready for display (translated) */ public function __toString() { return (string) $this->display('Name'); } /** * __isset() magic method for properties formerly returned by current_theme_info() * * @staticvar array $properties * * @return bool */ public function __isset( $offset ) { static $properties = array( 'name', 'title', 'version', 'parent_theme', 'template_dir', 'stylesheet_dir', 'template', 'stylesheet', 'screenshot', 'description', 'author', 'tags', 'theme_root', 'theme_root_uri', ); return in_array( $offset, $properties ); } /** * __get() magic method for properties formerly returned by current_theme_info() * * @return mixed */ public function __get( $offset ) { switch ( $offset ) { case 'name' : case 'title' : return $this->get('Name'); case 'version' : return $this->get('Version'); case 'parent_theme' : return $this->parent() ? $this->parent()->get('Name') : ''; case 'template_dir' : return $this->get_template_directory(); case 'stylesheet_dir' : return $this->get_stylesheet_directory(); case 'template' : return $this->get_template(); case 'stylesheet' : return $this->get_stylesheet(); case 'screenshot' : return $this->get_screenshot( 'relative' ); // 'author' and 'description' did not previously return translated data. case 'description' : return $this->display('Description'); case 'author' : return $this->display('Author'); case 'tags' : return $this->get( 'Tags' ); case 'theme_root' : return $this->get_theme_root(); case 'theme_root_uri' : return $this->get_theme_root_uri(); // For cases where the array was converted to an object. default : return $this->offsetGet( $offset ); } } /** * Method to implement ArrayAccess for keys formerly returned by get_themes() * * @param mixed $offset * @param mixed $value */ public function offsetSet( $offset, $value ) {} /** * Method to implement ArrayAccess for keys formerly returned by get_themes() * * @param mixed $offset */ public function offsetUnset( $offset ) {} /** * Method to implement ArrayAccess for keys formerly returned by get_themes() * * @staticvar array $keys * * @param mixed $offset * @return bool */ public function offsetExists( $offset ) { static $keys = array( 'Name', 'Version', 'Status', 'Title', 'Author', 'Author Name', 'Author URI', 'Description', 'Template', 'Stylesheet', 'Template Files', 'Stylesheet Files', 'Template Dir', 'Stylesheet Dir', 'Screenshot', 'Tags', 'Theme Root', 'Theme Root URI', 'Parent Theme', ); return in_array( $offset, $keys ); } /** * Method to implement ArrayAccess for keys formerly returned by get_themes(). * * Author, Author Name, Author URI, and Description did not previously return * translated data. We are doing so now as it is safe to do. However, as * Name and Title could have been used as the key for get_themes(), both remain * untranslated for back compatibility. This means that ['Name'] is not ideal, * and care should be taken to use $theme->display('Name') to get a properly * translated header. * * @param mixed $offset * @return mixed */ public function offsetGet( $offset ) { switch ( $offset ) { case 'Name' : case 'Title' : // See note above about using translated data. get() is not ideal. // It is only for backwards compatibility. Use display(). return $this->get('Name'); case 'Author' : return $this->display( 'Author'); case 'Author Name' : return $this->display( 'Author', false); case 'Author URI' : return $this->display('AuthorURI'); case 'Description' : return $this->display( 'Description'); case 'Version' : case 'Status' : return $this->get( $offset ); case 'Template' : return $this->get_template(); case 'Stylesheet' : return $this->get_stylesheet(); case 'Template Files' : return $this->get_files( 'php', 1, true ); case 'Stylesheet Files' : return $this->get_files( 'css', 0, false ); case 'Template Dir' : return $this->get_template_directory(); case 'Stylesheet Dir' : return $this->get_stylesheet_directory(); case 'Screenshot' : return $this->get_screenshot( 'relative' ); case 'Tags' : return $this->get('Tags'); case 'Theme Root' : return $this->get_theme_root(); case 'Theme Root URI' : return $this->get_theme_root_uri(); case 'Parent Theme' : return $this->parent() ? $this->parent()->get('Name') : ''; default : return null; } } /** * Returns errors property. * * @since 3.4.0 * @access public * * @return WP_Error|false WP_Error if there are errors, or false. */ public function errors() { return is_wp_error( $this->errors ) ? $this->errors : false; } /** * Whether the theme exists. * * A theme with errors exists. A theme with the error of 'theme_not_found', * meaning that the theme's directory was not found, does not exist. * * @since 3.4.0 * @access public * * @return bool Whether the theme exists. */ public function exists() { return ! ( $this->errors() && in_array( 'theme_not_found', $this->errors()->get_error_codes() ) ); } /** * Returns reference to the parent theme. * * @since 3.4.0 * @access public * * @return WP_Theme|false Parent theme, or false if the current theme is not a child theme. */ public function parent() { return isset( $this->parent ) ? $this->parent : false; } /** * Adds theme data to cache. * * Cache entries keyed by the theme and the type of data. * * @since 3.4.0 * @access private * * @param string $key Type of data to store (theme, screenshot, headers, page_templates) * @param string $data Data to store * @return bool Return value from wp_cache_add() */ private function cache_add( $key, $data ) { return wp_cache_add( $key . '-' . $this->cache_hash, $data, 'themes', self::$cache_expiration ); } /** * Gets theme data from cache. * * Cache entries are keyed by the theme and the type of data. * * @since 3.4.0 * @access private * * @param string $key Type of data to retrieve (theme, screenshot, headers, page_templates) * @return mixed Retrieved data */ private function cache_get( $key ) { return wp_cache_get( $key . '-' . $this->cache_hash, 'themes' ); } /** * Clears the cache for the theme. * * @since 3.4.0 * @access public */ public function cache_delete() { foreach ( array( 'theme', 'screenshot', 'headers', 'page_templates' ) as $key ) wp_cache_delete( $key . '-' . $this->cache_hash, 'themes' ); $this->template = $this->textdomain_loaded = $this->theme_root_uri = $this->parent = $this->errors = $this->headers_sanitized = $this->name_translated = null; $this->headers = array(); $this->__construct( $this->stylesheet, $this->theme_root ); } /** * Get a raw, unformatted theme header. * * The header is sanitized, but is not translated, and is not marked up for display. * To get a theme header for display, use the display() method. * * Use the get_template() method, not the 'Template' header, for finding the template. * The 'Template' header is only good for what was written in the style.css, while * get_template() takes into account where WordPress actually located the theme and * whether it is actually valid. * * @since 3.4.0 * @access public * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @return string|false String on success, false on failure. */ public function get( $header ) { if ( ! isset( $this->headers[ $header ] ) ) return false; if ( ! isset( $this->headers_sanitized ) ) { $this->headers_sanitized = $this->cache_get( 'headers' ); if ( ! is_array( $this->headers_sanitized ) ) $this->headers_sanitized = array(); } if ( isset( $this->headers_sanitized[ $header ] ) ) return $this->headers_sanitized[ $header ]; // If themes are a persistent group, sanitize everything and cache it. One cache add is better than many cache sets. if ( self::$persistently_cache ) { foreach ( array_keys( $this->headers ) as $_header ) $this->headers_sanitized[ $_header ] = $this->sanitize_header( $_header, $this->headers[ $_header ] ); $this->cache_add( 'headers', $this->headers_sanitized ); } else { $this->headers_sanitized[ $header ] = $this->sanitize_header( $header, $this->headers[ $header ] ); } return $this->headers_sanitized[ $header ]; } /** * Gets a theme header, formatted and translated for display. * * @since 3.4.0 * @access public * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @param bool $markup Optional. Whether to mark up the header. Defaults to true. * @param bool $translate Optional. Whether to translate the header. Defaults to true. * @return string|false Processed header, false on failure. */ public function display( $header, $markup = true, $translate = true ) { $value = $this->get( $header ); if ( false === $value ) { return false; } if ( $translate && ( empty( $value ) || ! $this->load_textdomain() ) ) $translate = false; if ( $translate ) $value = $this->translate_header( $header, $value ); if ( $markup ) $value = $this->markup_header( $header, $value, $translate ); return $value; } /** * Sanitize a theme header. * * @since 3.4.0 * @access private * * @staticvar array $header_tags * @staticvar array $header_tags_with_a * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @param string $value Value to sanitize. * @return mixed */ private function sanitize_header( $header, $value ) { switch ( $header ) { case 'Status' : if ( ! $value ) { $value = 'publish'; break; } // Fall through otherwise. case 'Name' : static $header_tags = array( 'abbr' => array( 'title' => true ), 'acronym' => array( 'title' => true ), 'code' => true, 'em' => true, 'strong' => true, ); $value = wp_kses( $value, $header_tags ); break; case 'Author' : // There shouldn't be anchor tags in Author, but some themes like to be challenging. case 'Description' : static $header_tags_with_a = array( 'a' => array( 'href' => true, 'title' => true ), 'abbr' => array( 'title' => true ), 'acronym' => array( 'title' => true ), 'code' => true, 'em' => true, 'strong' => true, ); $value = wp_kses( $value, $header_tags_with_a ); break; case 'ThemeURI' : case 'AuthorURI' : $value = esc_url_raw( $value ); break; case 'Tags' : $value = array_filter( array_map( 'trim', explode( ',', strip_tags( $value ) ) ) ); break; case 'Version' : $value = strip_tags( $value ); break; } return $value; } /** * Mark up a theme header. * * @since 3.4.0 * @access private * * @staticvar string $comma * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @param string $value Value to mark up. * @param string $translate Whether the header has been translated. * @return string Value, marked up. */ private function markup_header( $header, $value, $translate ) { switch ( $header ) { case 'Name' : if ( empty( $value ) ) { $value = esc_html( $this->get_stylesheet() ); } break; case 'Description' : $value = wptexturize( $value ); break; case 'Author' : if ( $this->get('AuthorURI') ) { $value = sprintf( '%2$s', $this->display( 'AuthorURI', true, $translate ), $value ); } elseif ( ! $value ) { $value = __( 'Anonymous' ); } break; case 'Tags' : static $comma = null; if ( ! isset( $comma ) ) { /* translators: used between list items, there is a space after the comma */ $comma = __( ', ' ); } $value = implode( $comma, $value ); break; case 'ThemeURI' : case 'AuthorURI' : $value = esc_url( $value ); break; } return $value; } /** * Translate a theme header. * * @since 3.4.0 * @access private * * @staticvar array $tags_list * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @param string $value Value to translate. * @return string Translated value. */ private function translate_header( $header, $value ) { switch ( $header ) { case 'Name' : // Cached for sorting reasons. if ( isset( $this->name_translated ) ) return $this->name_translated; $this->name_translated = translate( $value, $this->get('TextDomain' ) ); return $this->name_translated; case 'Tags' : if ( empty( $value ) || ! function_exists( 'get_theme_feature_list' ) ) return $value; static $tags_list; if ( ! isset( $tags_list ) ) { $tags_list = array(); $feature_list = get_theme_feature_list( false ); // No API foreach ( $feature_list as $tags ) $tags_list += $tags; } foreach ( $value as &$tag ) { if ( isset( $tags_list[ $tag ] ) ) { $tag = $tags_list[ $tag ]; } elseif ( isset( self::$tag_map[ $tag ] ) ) { $tag = $tags_list[ self::$tag_map[ $tag ] ]; } } return $value; default : $value = translate( $value, $this->get('TextDomain') ); } return $value; } /** * The directory name of the theme's "stylesheet" files, inside the theme root. * * In the case of a child theme, this is directory name of the child theme. * Otherwise, get_stylesheet() is the same as get_template(). * * @since 3.4.0 * @access public * * @return string Stylesheet */ public function get_stylesheet() { return $this->stylesheet; } /** * The directory name of the theme's "template" files, inside the theme root. * * In the case of a child theme, this is the directory name of the parent theme. * Otherwise, the get_template() is the same as get_stylesheet(). * * @since 3.4.0 * @access public * * @return string Template */ public function get_template() { return $this->template; } /** * Returns the absolute path to the directory of a theme's "stylesheet" files. * * In the case of a child theme, this is the absolute path to the directory * of the child theme's files. * * @since 3.4.0 * @access public * * @return string Absolute path of the stylesheet directory. */ public function get_stylesheet_directory() { if ( $this->errors() && in_array( 'theme_root_missing', $this->errors()->get_error_codes() ) ) return ''; return $this->theme_root . '/' . $this->stylesheet; } /** * Returns the absolute path to the directory of a theme's "template" files. * * In the case of a child theme, this is the absolute path to the directory * of the parent theme's files. * * @since 3.4.0 * @access public * * @return string Absolute path of the template directory. */ public function get_template_directory() { if ( $this->parent() ) $theme_root = $this->parent()->theme_root; else $theme_root = $this->theme_root; return $theme_root . '/' . $this->template; } /** * Returns the URL to the directory of a theme's "stylesheet" files. * * In the case of a child theme, this is the URL to the directory of the * child theme's files. * * @since 3.4.0 * @access public * * @return string URL to the stylesheet directory. */ public function get_stylesheet_directory_uri() { return $this->get_theme_root_uri() . '/' . str_replace( '%2F', '/', rawurlencode( $this->stylesheet ) ); } /** * Returns the URL to the directory of a theme's "template" files. * * In the case of a child theme, this is the URL to the directory of the * parent theme's files. * * @since 3.4.0 * @access public * * @return string URL to the template directory. */ public function get_template_directory_uri() { if ( $this->parent() ) $theme_root_uri = $this->parent()->get_theme_root_uri(); else $theme_root_uri = $this->get_theme_root_uri(); return $theme_root_uri . '/' . str_replace( '%2F', '/', rawurlencode( $this->template ) ); } /** * The absolute path to the directory of the theme root. * * This is typically the absolute path to wp-content/themes. * * @since 3.4.0 * @access public * * @return string Theme root. */ public function get_theme_root() { return $this->theme_root; } /** * Returns the URL to the directory of the theme root. * * This is typically the absolute URL to wp-content/themes. This forms the basis * for all other URLs returned by WP_Theme, so we pass it to the public function * get_theme_root_uri() and allow it to run the theme_root_uri filter. * * @since 3.4.0 * @access public * * @return string Theme root URI. */ public function get_theme_root_uri() { if ( ! isset( $this->theme_root_uri ) ) $this->theme_root_uri = get_theme_root_uri( $this->stylesheet, $this->theme_root ); return $this->theme_root_uri; } /** * Returns the main screenshot file for the theme. * * The main screenshot is called screenshot.png. gif and jpg extensions are also allowed. * * Screenshots for a theme must be in the stylesheet directory. (In the case of child * themes, parent theme screenshots are not inherited.) * * @since 3.4.0 * @access public * * @param string $uri Type of URL to return, either 'relative' or an absolute URI. Defaults to absolute URI. * @return string|false Screenshot file. False if the theme does not have a screenshot. */ public function get_screenshot( $uri = 'uri' ) { $screenshot = $this->cache_get( 'screenshot' ); if ( $screenshot ) { if ( 'relative' == $uri ) return $screenshot; return $this->get_stylesheet_directory_uri() . '/' . $screenshot; } elseif ( 0 === $screenshot ) { return false; } foreach ( array( 'png', 'gif', 'jpg', 'jpeg' ) as $ext ) { if ( file_exists( $this->get_stylesheet_directory() . "/screenshot.$ext" ) ) { $this->cache_add( 'screenshot', 'screenshot.' . $ext ); if ( 'relative' == $uri ) return 'screenshot.' . $ext; return $this->get_stylesheet_directory_uri() . '/' . 'screenshot.' . $ext; } } $this->cache_add( 'screenshot', 0 ); return false; } /** * Return files in the theme's directory. * * @since 3.4.0 * @access public * * @param mixed $type Optional. Array of extensions to return. Defaults to all files (null). * @param int $depth Optional. How deep to search for files. Defaults to a flat scan (0 depth). -1 depth is infinite. * @param bool $search_parent Optional. Whether to return parent files. Defaults to false. * @return array Array of files, keyed by the path to the file relative to the theme's directory, with the values * being absolute paths. */ public function get_files( $type = null, $depth = 0, $search_parent = false ) { $files = (array) self::scandir( $this->get_stylesheet_directory(), $type, $depth ); if ( $search_parent && $this->parent() ) $files += (array) self::scandir( $this->get_template_directory(), $type, $depth ); return $files; } /** * Returns the theme's page templates. * * @since 3.4.0 * @access public * * @param WP_Post|null $post Optional. The post being edited, provided for context. * @return array Array of page templates, keyed by filename, with the value of the translated header name. */ public function get_page_templates( $post = null ) { // If you screw up your current theme and we invalidate your parent, most things still work. Let it slide. if ( $this->errors() && $this->errors()->get_error_codes() !== array( 'theme_parent_invalid' ) ) return array(); $page_templates = $this->cache_get( 'page_templates' ); if ( ! is_array( $page_templates ) ) { $page_templates = array(); $files = (array) $this->get_files( 'php', 1 ); foreach ( $files as $file => $full_path ) { if ( ! preg_match( '|Template Name:(.*)$|mi', file_get_contents( $full_path ), $header ) ) continue; $page_templates[ $file ] = _cleanup_header_comment( $header[1] ); } $this->cache_add( 'page_templates', $page_templates ); } if ( $this->load_textdomain() ) { foreach ( $page_templates as &$page_template ) { $page_template = $this->translate_header( 'Template Name', $page_template ); } } if ( $this->parent() ) $page_templates += $this->parent()->get_page_templates( $post ); /** * Filter list of page templates for a theme. * * This filter does not currently allow for page templates to be added. * * @since 3.9.0 * * @param array $page_templates Array of page templates. Keys are filenames, * values are translated names. * @param WP_Theme $this The theme object. * @param WP_Post|null $post The post being edited, provided for context, or null. */ $return = apply_filters( 'theme_page_templates', $page_templates, $this, $post ); return array_intersect_assoc( $return, $page_templates ); } /** * Scans a directory for files of a certain extension. * * @since 3.4.0 * * @static * @access private * * @param string $path Absolute path to search. * @param array|string|null $extensions Optional. Array of extensions to find, string of a single extension, * or null for all extensions. Default null. * @param int $depth Optional. How many levels deep to search for files. Accepts 0, 1+, or * -1 (infinite depth). Default 0. * @param string $relative_path Optional. The basename of the absolute path. Used to control the * returned path for the found files, particularly when this function * recurses to lower depths. Default empty. * @return array|false Array of files, keyed by the path to the file relative to the `$path` directory prepended * with `$relative_path`, with the values being absolute paths. False otherwise. */ private static function scandir( $path, $extensions = null, $depth = 0, $relative_path = '' ) { if ( ! is_dir( $path ) ) return false; if ( $extensions ) { $extensions = (array) $extensions; $_extensions = implode( '|', $extensions ); } $relative_path = trailingslashit( $relative_path ); if ( '/' == $relative_path ) $relative_path = ''; $results = scandir( $path ); $files = array(); foreach ( $results as $result ) { if ( '.' == $result[0] ) continue; if ( is_dir( $path . '/' . $result ) ) { if ( ! $depth || 'CVS' == $result ) continue; $found = self::scandir( $path . '/' . $result, $extensions, $depth - 1 , $relative_path . $result ); $files = array_merge_recursive( $files, $found ); } elseif ( ! $extensions || preg_match( '~\.(' . $_extensions . ')$~', $result ) ) { $files[ $relative_path . $result ] = $path . '/' . $result; } } return $files; } /** * Loads the theme's textdomain. * * Translation files are not inherited from the parent theme. Todo: if this fails for the * child theme, it should probably try to load the parent theme's translations. * * @since 3.4.0 * @access public * * @return bool True if the textdomain was successfully loaded or has already been loaded. * False if no textdomain was specified in the file headers, or if the domain could not be loaded. */ public function load_textdomain() { if ( isset( $this->textdomain_loaded ) ) return $this->textdomain_loaded; $textdomain = $this->get('TextDomain'); if ( ! $textdomain ) { $this->textdomain_loaded = false; return false; } if ( is_textdomain_loaded( $textdomain ) ) { $this->textdomain_loaded = true; return true; } $path = $this->get_stylesheet_directory(); if ( $domainpath = $this->get('DomainPath') ) $path .= $domainpath; else $path .= '/languages'; $this->textdomain_loaded = load_theme_textdomain( $textdomain, $path ); return $this->textdomain_loaded; } /** * Whether the theme is allowed (multisite only). * * @since 3.4.0 * @access public * * @param string $check Optional. Whether to check only the 'network'-wide settings, the 'site' * settings, or 'both'. Defaults to 'both'. * @param int $blog_id Optional. Ignored if only network-wide settings are checked. Defaults to current blog. * @return bool Whether the theme is allowed for the network. Returns true in single-site. */ public function is_allowed( $check = 'both', $blog_id = null ) { if ( ! is_multisite() ) return true; if ( 'both' == $check || 'network' == $check ) { $allowed = self::get_allowed_on_network(); if ( ! empty( $allowed[ $this->get_stylesheet() ] ) ) return true; } if ( 'both' == $check || 'site' == $check ) { $allowed = self::get_allowed_on_site( $blog_id ); if ( ! empty( $allowed[ $this->get_stylesheet() ] ) ) return true; } return false; } /** * Returns array of stylesheet names of themes allowed on the site or network. * * @since 3.4.0 * * @static * @access public * * @param int $blog_id Optional. Defaults to current blog. * @return array Array of stylesheet names. */ public static function get_allowed( $blog_id = null ) { /** * Filter the array of themes allowed on the site or network. * * @since MU * * @param array $allowed_themes An array of theme stylesheet names. */ $network = (array) apply_filters( 'allowed_themes', self::get_allowed_on_network() ); return $network + self::get_allowed_on_site( $blog_id ); } /** * Returns array of stylesheet names of themes allowed on the network. * * @since 3.4.0 * * @static * @access public * * @staticvar array $allowed_themes * * @return array Array of stylesheet names. */ public static function get_allowed_on_network() { static $allowed_themes; if ( ! isset( $allowed_themes ) ) $allowed_themes = (array) get_site_option( 'allowedthemes' ); return $allowed_themes; } /** * Returns array of stylesheet names of themes allowed on the site. * * @since 3.4.0 * * @static * @access public * * @staticvar array $allowed_themes * * @param int $blog_id Optional. Defaults to current blog. * @return array Array of stylesheet names. */ public static function get_allowed_on_site( $blog_id = null ) { static $allowed_themes = array(); if ( ! $blog_id || ! is_multisite() ) $blog_id = get_current_blog_id(); if ( isset( $allowed_themes[ $blog_id ] ) ) return $allowed_themes[ $blog_id ]; $current = $blog_id == get_current_blog_id(); if ( $current ) { $allowed_themes[ $blog_id ] = get_option( 'allowedthemes' ); } else { switch_to_blog( $blog_id ); $allowed_themes[ $blog_id ] = get_option( 'allowedthemes' ); restore_current_blog(); } // This is all super old MU back compat joy. // 'allowedthemes' keys things by stylesheet. 'allowed_themes' keyed things by name. if ( false === $allowed_themes[ $blog_id ] ) { if ( $current ) { $allowed_themes[ $blog_id ] = get_option( 'allowed_themes' ); } else { switch_to_blog( $blog_id ); $allowed_themes[ $blog_id ] = get_option( 'allowed_themes' ); restore_current_blog(); } if ( ! is_array( $allowed_themes[ $blog_id ] ) || empty( $allowed_themes[ $blog_id ] ) ) { $allowed_themes[ $blog_id ] = array(); } else { $converted = array(); $themes = wp_get_themes(); foreach ( $themes as $stylesheet => $theme_data ) { if ( isset( $allowed_themes[ $blog_id ][ $theme_data->get('Name') ] ) ) $converted[ $stylesheet ] = true; } $allowed_themes[ $blog_id ] = $converted; } // Set the option so we never have to go through this pain again. if ( is_admin() && $allowed_themes[ $blog_id ] ) { if ( $current ) { update_option( 'allowedthemes', $allowed_themes[ $blog_id ] ); delete_option( 'allowed_themes' ); } else { switch_to_blog( $blog_id ); update_option( 'allowedthemes', $allowed_themes[ $blog_id ] ); delete_option( 'allowed_themes' ); restore_current_blog(); } } } return (array) $allowed_themes[ $blog_id ]; } /** * Sort themes by name. * * @since 3.4.0 * * @static * @access public */ public static function sort_by_name( &$themes ) { if ( 0 === strpos( get_locale(), 'en_' ) ) { uasort( $themes, array( 'WP_Theme', '_name_sort' ) ); } else { uasort( $themes, array( 'WP_Theme', '_name_sort_i18n' ) ); } } /** * Callback function for usort() to naturally sort themes by name. * * Accesses the Name header directly from the class for maximum speed. * Would choke on HTML but we don't care enough to slow it down with strip_tags(). * * @since 3.4.0 * * @static * @access private * * @return int */ private static function _name_sort( $a, $b ) { return strnatcasecmp( $a->headers['Name'], $b->headers['Name'] ); } /** * Name sort (with translation). * * @since 3.4.0 * * @static * @access private * * @return int */ private static function _name_sort_i18n( $a, $b ) { // Don't mark up; Do translate. return strnatcasecmp( $a->display( 'Name', false, true ), $b->display( 'Name', false, true ) ); } } JavaScript欲速则不达—原始值及原始值的隐式类型转换 》 html5jscss

JavaScript欲速则不达—原始值及原始值的隐式类型转换

我们知道在JavaScript中声明一个变量只需要要使用 var 操作符,后跟变量名,该变量就存在了,而该变量可以用来保存任何类型的数据。就是说变量的类型是根据所赋值的类型来决定自己的类型,所以一个变量到底是什么类型,不取决于变量定义本身,取决于它所包含的数据。数据类型决定着变量类型。

JavaScript中有五种原始类型值:Undefined、Null、Boolean、String、Number 。本文不讨论对象(包括数组和函数)

Undefined类型

Undefined类型只有一个值,即 undefined,中文意思就是未定义的意思,所以就跟这个单词所说一样,JavaScript中 未初始化 或者 未申明 的变量。而如果执行一个未申明的变了会导致一个错误,只能对其使用 typeof 操作符检测,如下

var name;
//var article
alert(name);//"undefined"
alert(article);//产生错误
alert(typeof name );//"undefined"
alert(typeof article );//"undefined"
未初始化和未申明的变量,typeof 运算符不会区分

虽然未初始化 或者 未申明本质上有区别,但是对于 Undefined类型 我们没有实际的操作价值。 Undefined类型 只有一个 undefined 值,另一种只有一个值的类型是 Null,值也就是它的字面量 null (首字母大写才是它们的类型,小写是他们的值)。

null 值从逻辑角度来看表示一个空对象指针,所以用 typeof 操作符检测null值会返回 object 。但是 Null 是没有值的,所以 Null不是任何数据类型的对象实例,因此alert(null instanceof Object); 返回false。

w3school上说:“值 undefined 实际上是从值 null 派生来的,因此 ECMAScript 把它们定义为相等的。”。null==undefined为真,但是null===undefined为假说明他们不是完全相等的。

var eq;
alert(eq==null); //ture
alert(eq===null);//false
alert(typeof null); //弹出 'object'
alert(null instanceof Object);//false
null与undefined大不同

注意:尽管null值和undefined有这样的关系,但是他们的用途大不相同。用 typeof 操作符检测 Null 会返回 object,所以 null值一般保存还没真正保存对象的变量,如你声明var doc = null为将来保存一个节点对象; 而undefined则没这个必要。

Boolean 类型

Boolean 类型是JavaScript中使用最多的一种类型,它只有两个字面量值:true和false。虽然true不一定等于1,false不一定等于0,但是JavaScript会在必要时将0转换成false。注意:在基本类型中undefined、null、””、0以及无关键字的数组等同于false的布尔值都是false,其他都是true。

原始的Boolean值和Boolean对象是有区别的,不要相互混淆。Boolean对象是对Boolean值的一个封装,是对一个值为true或false的Boolean对象,是不同概念的。

Number 类型

JavaScript中数值型是不区分整数和浮点数的,所以只要该数值包含一个小数点,并且小数点后面有至少一位数字,就是浮点数集。数值还可以通过十进制、八进制、十六进制的字面量表示,最基本的十进制。其中,八进制中如果字面值超出范围,那么后面的数值就当作十进制数值解析。如下:

var octalNum1 = 070 //八进制57,第一位是0表示按照8进制解析
var octalNum1 = 079//无效的八进制-解析成十进制79
var octalNum1 = 0x1f //十六进制31,0x开头表示安装十六进制解析
//其他格式则一律十进制
十进制、八进制、十六进制表示的数值

特殊的 Number 值有正负Infinity和NaN。

特殊的 Number 值NaN

是 Not a Number 的缩写,NaN表示某个值不是数值,但是其本身是特殊的数字值()。

NaN 与其他数值进行比较的结果总是不相等的,包括它自身在内。因此,不能用 Number.NaN 比较来检测一个值是不是数字,只能调用 isNaN() 来判断是不是 NaN。

var a = "234" ;
a = a.replace(/(^[//s]*)|([//s]*$)/g, "");
if( a !="" && !isNaN( a ) )
{
    a = eval( a ) //如果是数字
}
else
{
    a = null  //如果不是数字
}
判断是不是数字值

特殊的Infinity值

因为JavaScript中的数值是有限的,所以如果某个数值超出数值范围,那么这个数值将被自动转换成特殊的Infinity值。如果这个数是正,则会被表示成Infinity(正无穷大);这个数值是负无穷大,则会表示成-Infinity(负无穷大)。可以对任何数调用 isFinite()方法,以确保该数不是无穷大,返回true则是在范围之内;false则是范围之外

String类型

字符串(String)可以包含在双引号或者单引号里,字符串中的每个字符都有特定位置,所以可以通过访问length属性取得字符串的长度,首字符从位置 0 开始。因为在JavaScript中服从Unicode编码,所以不管是中文还是英文,length返回的都是字符串的个数。

特殊的字符串字面量(转义字符)

  1. \n  换行
  2. \t  制表
  3. \b  空格
  4. \f  回车
  5. \\  反斜杠
  6. \’  单引号
  7. \”  双引号

类型转换

转换成数值方法

var x = 3;
var y = x + "2";
var z = x + 2;
alert(x + "2")//输出32
alert( x + 2)//输出5

一般使用3个函数,eval()暂且不论。

  • parseFloat()和parseInt()只要开头是数字的非数值就能正确返回,有容错性。
  • parseFloat()和parseInt()遇到首字母是字母则返回NaN,不过parseInt()有两个参数,第二个参数决定将以几进制解析数值(16进制,你懂的)。
  • parseInt() 转换成整数,如果有小数点,只认识小数点前的数字值;parseFloat() 能转换浮点数,不过只能识别一个小数点,就是说第二个小数点和之后的字符无效。
  • Number()没有容错性,但是也有特殊情况:布尔值true会返回1,false值、null值、空字符串会返回0;其他只要不是阿拉伯数字统统返回NaN。
  • parseFloat()和parseInt()只处理字符串,Number()可以处理任何类型的。
var num1 = '1234abc';
var num2 = true;
var num3 = '4.5';
alert(parseInt(num1)); //输出1234,parseFloat输出一样
alert(Number(num1)); //输出NaN
alert(parseInt(num2));//输出NaN,parseFloat输出一样
alert(Number(num2));//输出1
alert(parseInt(num3));//输出4
alert(Number(num3));//输出4.5,parseFloat输出一样
数字值转换

转换成字符串方法

数值、布尔值、对象、字符串以及所有对象都有tostring()方法(null和undefined没有tostring()方法)。

ps:tostring()方法在调用数值的时,可以传递参数来决定以几进制返回字符串。规律如下:

  • 如果值有tostring()方法,则调用该方法
  • 如果值是null,则返回”null”
  • 如果值是undefined,则返回”undefined”

JavaScript中的隐式类型转换

var x = 4;
var y =x+"";
var a = '11';
a = a - "";
alert(typeof a);//number
alert(typeof x);//number
alert(typeof y);//string
alert(a);//11
alert(x + "3");//43
alert(x + 3);//7
alert("3"*x);//12

以上转换过程就是隐式转换的。

如上诉例子所示,”+”,”-“,”*”当然也包括”/”在运算中可以隐式得转换类型 。”+” 可以很方便的将Number转换成String;而”-“,”*”,”/”跟”+”正好相反,能将String类型转换成Number类型。

如果上下文需要boolean型的值,则引擎会自动将对象转换为boolean类型。转换规则:如果该对象非空,则转换为true,否则为false,所以null==undefined。

if跟while会把obj隐式的转换成Boolean类型;for in定义对象字面量时发生从标识符到字符串的隐式转换。

alert也会隐式类型转换。

假如给String原型上添加了个fn方法,该方法返回this,我们知道this可以理解成当前类的实例对象,既然是对象那么typeof a.fn()自然返回是object了。那么alert()该方法会是什么情况:

String.prototype.fn = function(){return this};
var a = 'hello';
alert(typeof a.fn()); //object
alert(a.fn());  //hello

很明显,alert() 语句隐式的将其转换成了字符串“hello”。

在基本数据类型隐式转换中做了如下几步骤:

  1. 基本类型值会先临时包装相对应的包装对象
  2. 采用操作方法后,直接销毁该对象(这里说的对象指一种类型,不是对象本身)。
var sr1 = "xiaobei";
var sr2 = sr1.substring(2);
alert(sr2); //aobei
sr1.color ="red";
alert(sr1.color);//undefined

以上代码说明,当调用substring方法来操作String基本类型时,JavaScript会自动包装一个临时的String对象,然后获取该对象的使用substring方法,调用完之后这个临时的对象就被摧毁,所以我们想给他增加一个color属性时,alert出来的是undefined。

因为是JavaScript自己创建基本包装对象的,所以我们叫它影式转换,跟显式的调用Boolean、Number跟String来创建包装对象对立。那么能影式将将基本类型转换成基本类型对象,JavaScript也可以隐式的将对象转换为基本类型,如下几步骤:

首先通过调用对象的valueOf()方法来取得对象的值,如果和上下文的类型匹配,则使用该值。如果valueOf取不到值的话,则需要调用对象的toString()方法,而如果上下文为数值型,则又需要将此字符串转换为数值。valueOf()的作用是,将一个对象的值转换成一种合乎上下文需求的基本类型,toString()则名副其实,可以打印出对象对应的字符串,当然前提是你已经“重载”了Object的toString()方法。

基本包装对象

因为有了基本包装类型,所以JavaScript中的基本类型值可以当作对象来访问,三种基本包装类型分别是:

  • Boolean(value) – 把给定的值转换成 Boolean 型;
  • Number(value) – 把给定的值转换成数字(可以是整数或浮点数);
  • String(value) – 把给定的值转换成字符串;

以上3中方法其实就是继承了valueOf()、toLocaleString()、和toString()方法,并且都重写了这些方法。这三种方法可以转换任何类型的数据。

JavaScript复杂数据类型(引用类型)包括数组(Array)、函数(function)、原始类型的引用类型(既通过Boolean(),Number(),String()创造的对象)以及JavaScript定义的一些专用对象类。其中函数(Function)是一个可调用的对象,不只是一组数据集合,是一段可执行的代码块。而且一个函数如果作为一个对象的属性(我们平时叫方法 method )。所以我觉得这就是为什么 typeof 操作符检测函数会返回 function 不返回 object的原因,作者是想告诉我们他们之间大不同。JavaScript的复杂类型这里就不详细介绍了。

本文源链接:http://www.html5jscss.com/js-data-type.html

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