diff --git a/demo/main.js b/demo/main.js
index b474c1d4b..3413f5815 100644
--- a/demo/main.js
+++ b/demo/main.js
@@ -203,7 +203,7 @@ class Demo extends Component {
     if (window.confirm(content)) {
       confirm();
     } else {
-      cancel();
+      cancel?.();
     }
   }