Fixes #5124: Added support to prevent duplicated form submission when using `ActiveForm`

framework/CHANGELOG.md

@@ -216,6 +216,7 @@ Yii Framework 2 Change Log
 - Enh #5058: Added `$pageSize` parameter to `Pagination::createUrl()` to allow creating URLs with arbitrary page sizes (cdcchen, qiangxue)
 - Enh #5089: Added asset debugger panel (arturf, qiangxue)
 - Enh #5117: Added `beforeFilter` and `afterFilter` JS events to `GridView` (kartik-v)
+- Enh #5124: Added support to prevent duplicated form submission when using `ActiveForm` (qiangxue)
 - Enh: Added support for using sub-queries when building a DB query with `IN` condition (qiangxue)
 - Enh: Supported adding a new response formatter without the need to reconfigure existing formatters (qiangxue)
 - Enh: Added `yii\web\UrlManager::addRules()` to simplify adding new URL rules (qiangxue)

framework/assets/yii.activeForm.js

@@ -349,11 +349,15 @@
                 data = $form.data('yiiActiveForm');
 
             if (data.validated) {
+                if (!data.submitting) {
+                    // form is being submitted. Do nothing to avoid duplicated form submission
+                    return false;
+                }
+                data.submitting = false;
                 var event = $.Event(events.beforeSubmit);
-                $form.trigger(event, [$form]);
+                $form.trigger(event);
                 if (event.result === false) {
                     data.validated = false;
-                    data.submitting = false;
                     return false;
                 }
                 return true;   // continue submitting the form since validation passes