这将检查后代关系，而不是严格的父子关系：

/**
 * Is the current page a descendent of page identified by the path (not slug).
 * A page is not a descendent of itself!
 * @param string $page_path The path of the page, e.g. mypage/mysubpage 
 * @return boolean True if current page is a descednent of specified $page_path. False otherwise.
 */
function is_descendent_of( $page_path ){

    if( !is_page() ){
        return false;
    }

    $ancestors = get_post_ancestors( get_queried_object_id() );
    $page = get_page_by_path( $page_path );
    if( $page )
        return in_array( $page->ID, $ancestors );
    return false;   
}

/**
 * Is the current page a child of the page identified by the path (not slug).
 * A page is not a child of itself! Child != descendant.
 * @param string $page_path The path of the page, e.g. mypage/mysubpage
 * @return boolean True if current page is a child of specified $page_path. False otherwise.
 */
function is_child_of( $page_path ){

    if( !is_page() ){
        return false;
    }

    $page = get_page_by_path( $page_path );
    $current_page = get_post();

    if( $page )
        return $current_page->post_parent == $page->ID;
    return false;
}

搜索此函数以与小部件逻辑一起使用，我发现this snippet, 适应波纹管：

/**
 * Check if a page is child of another 
 * 
 * @param mixed $page_id_or_slug Provide the parent ID or Slug
 * @return bool Whether the page is child or not of the given parent
 */
function is_child( $page_id_or_slug ) 
{ 
    global $post; 
    if( !is_page() )
        return false;

    # Slug provided, get ID
    if( !is_int( $page_id_or_slug ) ) 
    {
        $page = get_page_by_path( $page_id_or_slug );
        $page_id_or_slug = $page->ID;
    } 

    return $post->post_parent == $page_id_or_slug; 
}