From 5de37ea3216d2422554d3c194ffa0faa670a0271 Mon Sep 17 00:00:00 2001
From: Paul Holden <paulh@moodle.com>
Date: Thu, 21 Mar 2024 15:02:34 +0000
Subject: [PATCH] MDL-81320 datafield_checkbox: account for empty field
 content.

---
 mod/data/field/checkbox/field.class.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mod/data/field/checkbox/field.class.php b/mod/data/field/checkbox/field.class.php
index 3f47aa316ba..d022e9b1477 100644
--- a/mod/data/field/checkbox/field.class.php
+++ b/mod/data/field/checkbox/field.class.php
@@ -60,7 +60,7 @@ class data_field_checkbox extends data_field_base {
             $content = $formdata->$fieldname ?? [];
         } else if ($recordid) {
             $content = $DB->get_field('data_content', 'content', ['fieldid' => $this->field->id, 'recordid' => $recordid]);
-            $content = explode('##', $content);
+            $content = explode('##', $content ?? '');
         } else {
             $content = [];
         }