is_random_header_image( string $type = 'any' ): bool
- Since
- 3.2.0
- Source
wp-includes/theme.php:1467
Description
Always true if user expressly chooses the option in Appearance > Header.
Also true if theme has multiple header images registered, no specific header image is chosen, and theme turns on random headers with add_theme_support().
Compatibility
- WordPress
- since 3.2.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$typestringoptional- The random pool to use. Possible values include 'any', 'default', 'uploaded'. Default 'any'.Default:
'any'
Return value
bool
Performance profile
How much work a call to is_random_header_image() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Trivial
- Scaling
- Constant
- Instructions
- 15–26
- Plugin surface
- None
- Called by
- 4
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 39.
Nothing here hands control to plugin code.
4 places in core call this, so the cost is paid more often than your own code shows.
What it touches
- hookthird-party callbacks
apply_filters()one call below is_random_header_image()
Further down the call graph this can also reach option, cache, serialize, query and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost is_random_header_image() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 15–22 | get_theme_support(), get_theme_mod() |
empty($header_image_mod) | 23–26 | get_theme_support(), get_theme_mod(), get_random_header_image() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 39 instructions, 15–26 executed per call, 9 branches. The work does not change between versions.
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Uses · 3
- get_theme_mod()Retrieves theme modification value for the active theme.
- get_theme_support()Gets the theme support arguments passed when registering that support.
- get_random_header_image()Gets random header image URL from registered images in theme.
Used by · 4
- Custom_Image_Header::show_header_selector()Displays UI for selecting one of several default headers.
- get_custom_header()Gets the header image data.
- get_header_image()Retrieves header image for custom header.
- get_media_states()Retrieves an array of media states from an attachment.
Source code
function is_random_header_image( $type = 'any' ) { $header_image_mod = get_theme_mod( 'header_image', get_theme_support( 'custom-header', 'default-image' ) ); if ( 'any' === $type ) { if ( 'random-default-image' === $header_image_mod || 'random-uploaded-image' === $header_image_mod || ( empty( $header_image_mod ) && '' !== get_random_header_image() ) ) { return true; } } else { if ( "random-$type-image" === $header_image_mod ) { return true; } elseif ( 'default' === $type && empty( $header_image_mod ) && '' !== get_random_header_image() ) { return true; } } return false;}Changelog
Introduced in 3.2.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 7.0.4 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
- Something wrong on this page? Report it and it gets fixed in the next regeneration.