diff --git a/packages/masamune/lib/form/form_scoped_widget.dart b/packages/masamune/lib/form/form_scoped_widget.dart
index b69af267a..9430e4662 100644
--- a/packages/masamune/lib/form/form_scoped_widget.dart
+++ b/packages/masamune/lib/form/form_scoped_widget.dart
@@ -63,6 +63,17 @@ class FormRef implements WidgetRef {
 
   @override
   WidgetScopedValueRef get widget => _widgetRef.widget;
+
+  /// When a value is being added to a form, [onAdd] is executed; when editing, [onEdit] is executed.
+  ///
+  /// フォームに値を追加しているときは[onAdd]が実行され、編集しているときは[onEdit]が実行されます。
+  T? select<T>({T Function()? onAdd, T Function(String? editId)? onEdit}) {
+    if (isAdding) {
+      return onAdd?.call();
+    } else {
+      return onEdit?.call(editId);
+    }
+  }
 }
 
 /// Abstract class to implement the View portion of the form widget used to both add new and edit existing forms.