diff --git a/handlers/upload/templates/form.html.tpl b/handlers/upload/templates/form.html.tpl
index 986766b..bfd048e 100644
--- a/handlers/upload/templates/form.html.tpl
+++ b/handlers/upload/templates/form.html.tpl
@@ -94,13 +94,14 @@
   {{ end }}
 </body>
 <script type="text/javascript">
+  var isSuccess = {{.IsSuccess }};
   var submit = document.getElementById("submit");
   submit.addEventListener("submit", function () {
     submit.disabled = true;
   });
-  { { if .IsSuccess } }
-  alert("file uploaded successfully");
-  { { end } }
+  if (isSuccess) {
+    alert("file uploaded successfully");
+  }
 </script>
 
 </html>
\ No newline at end of file