wp-includes/rest-api/class-wp-rest-request.php:314Retrieves the Content-Type of the request.
array|null public function get_content_type() { $value = $this->get_header( 'Content-Type' ); if ( empty( $value ) ) { return null; } $parameters = ''; if ( strpos( $value, ';' ) ) { list( $value, $parameters ) = explode( ';', $value, 2 ); } $value = strtolower( $value ); if ( ! str_contains( $value, '/' ) ) { return null; } // Parse type and subtype out. list( $type, $subtype ) = explode( '/', $value, 2 ); $data = compact( 'value', 'type', 'subtype', 'parameters' ); $data = array_map( 'trim', $data ); return $data; }Introduced in 4.4.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/rest-api/class-wp-rest-request.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.