Set order by custom field value 'lastname'

cvd-theme/functions.php

@@ -28,6 +28,24 @@ function set_acf_settings() {
 
 add_filter( 'acf/shortcode/allow_in_block_themes_outside_content', '__return_true' );
 
+// Order by custom field value by meta_key 'lastname'
+function my_pre_get_posts( $query ) { 
+    // do not modify queries in the admin
+    if( is_admin() ) {
+        return $query;       
+    }
+    // only modify queries for 'event' post type
+    if( isset($query->query_vars['post_type']) && $query->query_vars['post_type']) { 
+        $query->set('orderby', 'meta_value');    
+        $query->set('meta_key', 'lastname');    
+        $query->set('order', 'ASC');    
+    }
+    // return
+    return $query;
+}
+
+add_action('pre_get_posts', 'my_pre_get_posts');
+
 
 // General Settings - Set Default Featured Image Placeholder if none exists
 if ( ! class_exists( 'DefaultThumbnailID' ) ) {
@@ -86,4 +104,4 @@ if ( ! class_exists( 'DefaultThumbnailID' ) ) {
     DefaultThumbnailID::get_instance();
     }
 
-?>
+