Reply To: Check if value already exist

• John Huebner

• January 4, 2016 at 3:05 am

This could be done, but not directly, it will take a little work. What you’d need to do is set up an acf/validate_value filter outlined here http://www.advancedcustomfields.com/resources/acf-validate_value/

In the filter you can then do a query of all of the posts to see if there is another post with the same field value and return an error. Something along the lines of:

add_filter('acf/validate_value/name=field_name', 
            'validate_field_name_filter, 10, 4)
function validate_field_name_filter($valid, $value, $field, $input) {
  if (!$valid || $value == '') {
    return $valid;
  }
  // query posts for the same value
  // for more info see
  // http://codex.wordpress.org/Class_Reference/WP_Query
  global $post; 
  $args = array(
    'post_type' => 'post',  // or your post
    'post__not_in' => array($post->ID), // do not check this post
    'meta_query' => array(
      array(
        'key' => 'field_name',
        'value' => $value
      )
    )
  );
  $query = new WP_Query($args);
  if (count($query->posts)) {
    // found at least one post that
    // already has $value
    $valid = 'There is already a post using this video';
  }
  return $valid;
}