你必须过滤user_has_cap 并比较用户元字段。

以下代码基于this answer 和未测试。

add_filter( \'user_has_cap\', \'wpse_99393_filter_cap\', 10, 3 );

/**
 * Allow editing others posts only for editors from the same school.
 * Administrators can still edit those posts.
 *
 * @wp-hook user_has_cap
 * @param   array $allcaps All the capabilities of the user
 * @param   array $caps    [0] Required capability (\'edit_others_posts\')
 * @param   array $args    [0] Requested capability
 *                         [1] User ID
 *                         [2] Post ID
 * @return  array
 */
function wpse_99393_filter_cap( $allcaps, $caps, $args )
{
    // Not our capability
    if ( \'edit_post\' !== $args[0] && \'delete_post\' !== $args[0] )
        return $allcaps;

    $post = get_post( $args[2] );

    // Let users edit their own posts
    if ( (int) $args[1] === (int) $post->post_author )
        $allcaps[ $caps[0] ] = TRUE;

    // editor meta field is set and not empty
    if ( ! $editor_school = get_user_meta( $args[1], \'school\', TRUE ) )
        return $allcaps;

    // author meta field is set and not empty
    if ( ! $author_school = get_user_meta( $post->post_author, \'school\', TRUE ) )
        return $allcaps;

    if ( $author_school === $editor_school )
        $allcaps[ $caps[0] ] = TRUE;

    return $allcaps;
}