Obtain page data and use regular loop

Question

Is there a way to obtain the data from a certain page outside the regular flow, more efficiently than via get_post($id)? I know that I can get for example the title with

$post = get_post($id);
$title = $post->post_title;

But I prefer to use the loop, rather than picking every single page element in the way I described above. So what I want, is to read the entire page data, and then perform a 'regular loop', using the_title(), the_content(), the_post_thumbnail() etc.

The reason why I ask this is because I'm busy creating a '404 solution' for my theme, where one is able to create and edit a custom 404 page in the WordPress backend.

Answer 1

You need to use setup_postdata().

$post = get_post( $id );
setup_postdata( $post );

if(! empty( $post ) ){
  the_title(); 
  echo '<br>';
  the_content();
}
else {
  echo "No page found matching ID $id";
}