WordPress函数is_active_sidebar()

$index

(mixed) (必填) 侧边栏名称或ID.

默认值: None

示例：

<?php if ( is_active_sidebar( 'left-sidebar' ) ) { ?>
	<ul id="sidebar">
		<?php dynamic_sidebar( 'left-sidebar' ); ?>
	</ul>
<?php } ?>

源文件：

/**
 * Whether a sidebar is in use.
 *
 * @since 2.8.0
 *
 * @param string|int $index Sidebar name, id or number to check.
 * @return bool true if the sidebar is in use, false otherwise.
 */
function is_active_sidebar( $index ) {
	$index = ( is_int($index) ) ? "sidebar-$index" : sanitize_title($index);
	$sidebars_widgets = wp_get_sidebars_widgets();
	$is_active_sidebar = ! empty( $sidebars_widgets[$index] );

	/**
	 * Filter whether a dynamic sidebar is considered "active".
	 *
	 * @since 3.9.0
	 *
	 * @param bool       $is_active_sidebar Whether or not the sidebar should be considered "active".
	 *                                      In other words, whether the sidebar contains any widgets.
	 * @param int|string $index             Index, name, or ID of the dynamic sidebar.
	 */
	return apply_filters( 'is_active_sidebar', $is_active_sidebar, $index );
}

/* Internal Functions */