Display a specified content on a Page and all its child pages

Question

I have a website with 5 main pages (consider them as sections), then 3-5 sub pages for each of them. I would like to display a flash banner for each section, i.e. it should display the flash banner on that page and all its sub pages.

Right now i am able to get that o the main page by using the following code.

<?php if (is_page('our-school-district')) { ?>
                    <object width="664" height="217">
                        <param name="movie" value="<?php bloginfo('url'); ?>/wp-content/uploads/2011/03/school_district.swf" />
                        <param name="wmode" value="transparent" />
                        <embed src="<?php bloginfo('url'); ?>/wp-content/uploads/2011/03/school_district.swf" width="664" height="217" wmode="transparent"></embed>
                        <!-- It Is Not Just About The Seeds That Are Planted, but the Garden That Surrounds Them. -->
                    </object>                    
                    <?php } ?>

How do I get it on all sub pages too?

Answer 1

You can do that by using this nice little function:

function is_page_or_child_of($slug){
    global $post;
    if (empty($slug))
        return false;
    //is it the page?
    if ($post->post_name = $slug) 
        return true;
    //check the children
    $page = get_page_by_path($slug);
    $children = get_pages('child_of='.$page->ID.'&sort_column=post_date&sort_order=desc');
    foreach ($children as $sub){
        if ($post->ID == $sub->ID){
            return true;
        }
    }
    return false;
}

and instead of using is_page('our-school-district') use s_page_or_child_of('our-school-district')

Answer 2

You should create a template for each page that way you can add the banner directly to it without having to mess with a bunch of php unless the banner will be outside of the page template view this link for a better explanation Wordpress Codex - Pages