wp_get_custom_css( string $stylesheet = '' ): string

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$stylesheetstringoptional

A theme object stylesheet name. Defaults to the active theme.Default: ''

Return value

string

The Custom CSS Post content.

Performance profile

How much work a call to wp_get_custom_css() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Heavy

Reaches the database via get_post().

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

16–21

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 21.

Plugin surface

1 hook

Third-party callbacks on 'wp_get_custom_css' run inside this call, and their cost is not bounded by anything here.

Called by

3

3 places in core call this, so the cost is paid more often than your own code shows.

What it touches

• hookthird-party callbacksapply_filters()called directly
• optionoption read or writeget_option()one call below wp_get_custom_css()
• querycontent queryget_post()one call below wp_get_custom_css()

Further down the call graph this can also reach cache, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 2 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_get_custom_css() can have, taken from its control-flow graph on PHP 8.5.

Hooks and filters fired · 1

One hook fires while wp_get_custom_css() runs, in this order:

1. 1
   apply_filters( wp_get_custom_css )filterline 2050 (+20 into the body)

   Filters the custom CSS output into the head element.

Uses · 3

• get_stylesheet()Retrieves name of the current stylesheet.
• wp_get_custom_css_post()Fetches the `custom_css` post for a given theme.
• apply_filters()Calls the callback functions that have been added to a filter hook.

Used by · 3

• wp_custom_css_cb()Renders the Custom CSS style element.
• wp_enqueue_global_styles()Enqueues the global styles defined via theme.json.
• wp_enqueue_global_styles_custom_css()Enqueues the global styles custom css defined via theme.json.

Source code

View on Trac ↗View on GitHub ↗

2030function wp_get_custom_css( $stylesheet = '' ) {2031	$css = '';2032 2033	if ( empty( $stylesheet ) ) {2034		$stylesheet = get_stylesheet();2035	}2036 2037	$post = wp_get_custom_css_post( $stylesheet );2038	if ( $post ) {2039		$css = $post->post_content;2040	}2041 2042	/**2043	 * Filters the custom CSS output into the head element.2044	 *2045	 * @since 4.7.02046	 *2047	 * @param string $css        CSS pulled in from the Custom CSS post type.2048	 * @param string $stylesheet The theme stylesheet name.2049	 */2050	$css = apply_filters( 'wp_get_custom_css', $css, $stylesheet );2051 2052	return $css;2053}

Changelog

Introduced in 4.7.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 6.8.8 tag, from src/wp-includes/theme.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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