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<?php
//take relationship field of this doctor
$location= get_field('location');
if( $location):
foreach( $location as $l ):
//array of post type doctor and take the post with key location and compare with the ID of location of this doctor $l->ID
$doctors = get_posts(array(
'post_type' => 'doctor',
'posts_per_page' => '-1',
'post__not_in' => [get_queried_object_id()],
'meta_query' => array(
array(
'key' => 'location', // name of custom field
'value' => $l->ID, // the ID of this doctor
'compare' => 'LIKE'
)
)
));
?>
<?php if( $doctors ): ?>
<?php foreach( $doctors as $doctor ): ?>
//
<div class="col-md-2">
<a href="<?php echo get_permalink( $doctor->ID ); ?>">
<img src="<?php echo get_the_post_thumbnail_url( $doctor->ID ); ?>">
<h2><?php echo get_the_title( $doctor->ID ); ?></h2>
</a>
</div>
<?php endforeach; ?> //second foreach
<?php endif; ?> //second if
<?php endforeach; ?> //first foreach
<?php endif; ?> //first if
