odd behaviours from template tags

Question

Some of my template tags are playing up, and they have left me confused.

On one site, that has been live for over a year without any of these issues, on all the pages that have custom query loops, the_content() was repeating the first entry. I replaced that line with echo get_the_cotent($post->ID), which I thought was totally equivalent, and it solved the problem.

Now, I have a very similar issue with another site. Trying to fetch and display content from child pages, I have this code block:

global $post;
$my_wp_query = new WP_Query();
$all_wp_pages = $my_wp_query->query(array('post_type' => 'page'));
$children = get_page_children($post->ID,$all_wp_pages);
foreach($children as $child){

    ?>
    <div class="childPage">
    <h3><?php the_title($child->ID); ?></h3>
    </div>  
    <?php
}

but this just repeats the title of the parent page.

However, if I replace the_title with echo get_the_title( is works as expected.

I am only assuming these are comparable issues, the certainly have similar symptoms and solutions.

Answer 1

Post ID is not an argument in the_title() (see Codex article). Accepted arguments are:

the_title( $before, $after, $echo );

Take a look at the source code. The function the_title() calls get_the_title() with no arguments, whereas get_the_title() takes a Post ID as its only argument. If you want the title of a post/page other than the current one in the query, stick with echo get_the_title(....

Edit: BTW, Post ID is an argument for neither the_content() nor get_the_content().