get_site_url( int|null $blog_id = null, string $path = '', string|null $scheme = null ): string

3526function get_site_url( $blog_id = null, $path = '', $scheme = null ) {3527	if ( empty( $blog_id ) || ! is_multisite() ) {3528		$url = get_option( 'siteurl' );3529	} else {3530		switch_to_blog( $blog_id );3531		$url = get_option( 'siteurl' );3532		restore_current_blog();3533	}3534 3535	$url = set_url_scheme( $url, $scheme );3536 3537	if ( $path && is_string( $path ) ) {3538		$url .= '/' . ltrim( $path, '/' );3539	}3540 3541	/**3542	 * Filters the site URL.3543	 *3544	 * @since 2.7.03545	 *3546	 * @param string      $url     The complete site URL including scheme and path.3547	 * @param string      $path    Path relative to the site URL. Blank string if no path is specified.3548	 * @param string|null $scheme  Scheme to give the site URL context. Accepts 'http', 'https', 'login',3549	 *                             'login_post', 'admin', 'relative' or null.3550	 * @param int|null    $blog_id Site ID, or null for the current site.3551	 */3552	return apply_filters( 'site_url', $url, $path, $scheme, $blog_id );3553}