Question

I am writing a wordpress plugin and want to add a meta_box for all types of posts (‘page’, ‘post’, ‘custom_post_type’). By referring the wordpress add_meta_box() I found it accepts only single type of post. Does anybody know how to do what I want? Thanks.

Answer 1

foreach ( array( 'post', 'page', 'custom_whatever', 'whatever2' ) as $page )
    add_meta_box( 'id', 'whatever', $callback, $page, $context, $priority, $callback_args );

Note that now $page becomes an array, and ittirating through it , will get you all post types.

Update I

You can get all the registered post types with get_post_types and use it to populate the above array.

(note : you might need to filter and get attachments out of the array..)