• John Huebner

• November 15, 2015 at 8:43 am

It doesn’t look like there is a way built into ACF, though it would be a good addition.

It could be done, you’d need to create another fields to use for the excerpt and then create a filter, either acf/pre_save_post or acf/save_post to take the value from the field and put it into the excerpt.

If you use the latter (acf/save_post) be careful of creating a save post infinite loop.

add_action('acf/save_post', 'my_save_post_filter', 20);
function my_save_post_filter($post_id) {
  if (get_post_type($post_id) != 'your-post-type')) {
    return;
  }
  // remove this filter to avoid infinite loop
  remove_filter('acf/save_post', 'my_save_post_filter', 20);
  
  // get your value and update post
  // see https://codex.wordpress.org/Function_Reference/wp_update_post
  
  // put this filter back in place
  add_action('acf/save_post', 'my_save_post_filter', 20);
}