Reply To: Only Display Custom Field Choices with Posts

• John Huebner

• April 10, 2016 at 11:27 pm

It will be different depending on if the select field on the post allows a single choice or multiple choices.

With a custom field you’re going to need to do a WP_Query for every name in the loop. http://codex.wordpress.org/Class_Reference/WP_Query

// select single
// all of this goes inside your foreach loop
$args = array(
  'post_type' => 'post',
  'posts_per_page' => 1, // only need 1, just checking for any posts with the value
  'meta_query' => array(
    array(
      'key' => 'family_name'
      'value' => $family
    )
  ) 
)
$query = new WP_Query($args);
if (count($query->posts)) {
  echo '<li>' . $family . '</li>';
)

// multiple choices allowed
// all of this goes inside your foreach loop
$args = array(
  'post_type' => 'post',
  'posts_per_page' => 1, // only need 1, just checking for any posts with the value
  'meta_query' => array(
    array(
      'key' => 'family_name'
      'value' => '"'.$family.'"',
      'compare => 'LIKE'
    )
  ) 
)
$query = new WP_Query($args);
if (count($query->posts)) {
  echo '<li>' . $family . '</li>';
)

Either way, if there are a lot of choices then this is going to be extremely slow. You would be better off in the long run to use a custom taxonomy, something that’s built right into WP, then you just need to use get_terms() with the right arguments https://developer.wordpress.org/reference/functions/get_terms/