* Dependencies API: WP_Styles class
* @subpackage Dependencies
* Core class used to register styles.
class WP_Styles extends WP_Dependencies {
* Full URL with trailing slash.
* URL of the content directory.
* Default version string for stylesheets.
* The current text direction.
public $text_direction = 'ltr';
* Holds a list of style handles which will be concatenated.
* Holds a string which contains style handles and their version.
public $concat_version = '';
* Whether to perform concatenation.
public $do_concat = false;
* Holds HTML markup of styles and additional data if concatenation
* Holds inline styles if concatenation is enabled.
* List of default directories.
* Holds a string which contains the type attribute for style tag.
* If the current theme does not declare HTML5 support for 'style',
* then it initializes as `type='text/css'`.
public function __construct() {
function_exists( 'is_admin' ) && ! is_admin()
function_exists( 'current_theme_supports' ) && ! current_theme_supports( 'html5', 'style' )
$this->type_attr = " type='text/css'";
* Fires when the WP_Styles instance is initialized.
* @param WP_Styles $this WP_Styles instance (passed by reference).
do_action_ref_array( 'wp_default_styles', array( &$this ) );
* Processes a style dependency.
* @since 5.5.0 Added the `$group` parameter.
* @see WP_Dependencies::do_item()
* @param string $handle The style's registered handle.
* @param int|false $group Optional. Group level: level (int), no groups (false).
* @return bool True on success, false on failure.
public function do_item( $handle, $group = false ) {
if ( ! parent::do_item( $handle ) ) {
$obj = $this->registered[ $handle ];
if ( null === $obj->ver ) {
$ver = $obj->ver ? $obj->ver : $this->default_version;
if ( isset( $this->args[ $handle ] ) ) {
$ver = $ver ? $ver . '&' . $this->args[ $handle ] : $this->args[ $handle ];
$conditional = isset( $obj->extra['conditional'] ) ? $obj->extra['conditional'] : '';
$cond_before = "<!--[if {$conditional}]>\n";
$cond_after = "<![endif]-->\n";
$inline_style = $this->print_inline_style( $handle, false );
$inline_style_tag = sprintf(
"<style id='%s-inline-css'%s>\n%s\n</style>\n",
if ( $this->do_concat ) {
if ( $this->in_default_dir( $src ) && ! $conditional && ! isset( $obj->extra['alt'] ) ) {
$this->concat .= "$handle,";
$this->concat_version .= "$handle$ver";
$this->print_code .= $inline_style;
if ( isset( $obj->args ) ) {
$media = esc_attr( $obj->args );
// A single item may alias a set of items, by having dependencies, but no source.
if ( $inline_style_tag ) {
if ( $this->do_concat ) {
$this->print_html .= $inline_style_tag;
$href = $this->_css_href( $src, $ver, $handle );
$rel = isset( $obj->extra['alt'] ) && $obj->extra['alt'] ? 'alternate stylesheet' : 'stylesheet';
$title = isset( $obj->extra['title'] ) ? sprintf( "title='%s'", esc_attr( $obj->extra['title'] ) ) : '';
"<link rel='%s' id='%s-css' %s href='%s'%s media='%s' />\n",
* Filters the HTML link tag of an enqueued style.
* @since 4.3.0 Introduced the `$href` parameter.
* @since 4.5.0 Introduced the `$media` parameter.
* @param string $html The link tag for the enqueued style.
* @param string $handle The style's registered handle.
* @param string $href The stylesheet's source URL.
* @param string $media The stylesheet's media attribute.
$tag = apply_filters( 'style_loader_tag', $tag, $handle, $href, $media );
if ( 'rtl' === $this->text_direction && isset( $obj->extra['rtl'] ) && $obj->extra['rtl'] ) {
if ( is_bool( $obj->extra['rtl'] ) || 'replace' === $obj->extra['rtl'] ) {
$suffix = isset( $obj->extra['suffix'] ) ? $obj->extra['suffix'] : '';
$rtl_href = str_replace( "{$suffix}.css", "-rtl{$suffix}.css", $this->_css_href( $src, $ver, "$handle-rtl" ) );
$rtl_href = $this->_css_href( $obj->extra['rtl'], $ver, "$handle-rtl" );
"<link rel='%s' id='%s-rtl-css' %s href='%s'%s media='%s' />\n",
/** This filter is documented in wp-includes/class.wp-styles.php */
$rtl_tag = apply_filters( 'style_loader_tag', $rtl_tag, $handle, $rtl_href, $media );
if ( 'replace' === $obj->extra['rtl'] ) {
if ( $this->do_concat ) {
$this->print_html .= $cond_before;
$this->print_html .= $tag;
if ( $inline_style_tag ) {
$this->print_html .= $inline_style_tag;
$this->print_html .= $cond_after;
$this->print_inline_style( $handle );
* Adds extra CSS styles to a registered stylesheet.
* @param string $handle The style's registered handle.
* @param string $code String containing the CSS styles to be added.
* @return bool True on success, false on failure.
public function add_inline_style( $handle, $code ) {
$after = $this->get_data( $handle, 'after' );
return $this->add_data( $handle, 'after', $after );
* Prints extra CSS styles of a registered stylesheet.
* @param string $handle The style's registered handle.
* @param bool $echo Optional. Whether to echo the inline style
* instead of just returning it. Default true.
* @return string|bool False if no data exists, inline styles if `$echo` is true,
public function print_inline_style( $handle, $echo = true ) {
$output = $this->get_data( $handle, 'after' );
if ( empty( $output ) ) {
$output = implode( "\n", $output );
"<style id='%s-inline-css'%s>\n%s\n</style>\n",
* Determines style dependencies.
* @see WP_Dependencies::all_deps()
* @param string|string[] $handles Item handle (string) or item handles (array of strings).
* @param bool $recursion Optional. Internal flag that function is calling itself.
* @param int|false $group Optional. Group level: level (int), no groups (false).
* @return bool True on success, false on failure.
public function all_deps( $handles, $recursion = false, $group = false ) {
$r = parent::all_deps( $handles, $recursion, $group );
* Filters the array of enqueued styles before processing for output.
* @param string[] $to_do The list of enqueued style handles about to be processed.
$this->to_do = apply_filters( 'print_styles_array', $this->to_do );
* Generates an enqueued style's fully-qualified URL.
* @param string $src The source of the enqueued style.
* @param string $ver The version of the enqueued style.
* @param string $handle The style's registered handle.
* @return string Style's fully-qualified URL.
public function _css_href( $src, $ver, $handle ) {
if ( ! is_bool( $src ) && ! preg_match( '|^(https?:)?//|', $src ) && ! ( $this->content_url && 0 === strpos( $src, $this->content_url ) ) ) {
$src = $this->base_url . $src;
$src = add_query_arg( 'ver', $ver, $src );
* Filters an enqueued style's fully-qualified URL.
* @param string $src The source URL of the enqueued style.
* @param string $handle The style's registered handle.
$src = apply_filters( 'style_loader_src', $src, $handle );
* Whether a handle's source is in a default directory.
* @param string $src The source of the enqueued style.
* @return bool True if found, false if not.
public function in_default_dir( $src ) {
if ( ! $this->default_dirs ) {
foreach ( (array) $this->default_dirs as $test ) {
if ( 0 === strpos( $src, $test ) ) {
* Processes items and dependencies for the footer group.
* HTML 5 allows styles in the body, grab late enqueued items and output them in the footer.
* @see WP_Dependencies::do_items()
* @return string[] Handles of items that have been processed.
public function do_footer_items() {
$this->do_items( false, 1 );
* Resets class properties.
public function reset() {
$this->do_concat = false;
$this->concat_version = '';