diff --git a/app/controller/Index.php b/app/controller/Index.php
index a31c7eb..36988e2 100644
--- a/app/controller/Index.php
+++ b/app/controller/Index.php
@@ -138,7 +138,7 @@ class Index extends BaseController
     {
 
     }
-    private function clearDirectory($dir)
+    private function clearDirectory($dir): bool
     {
         // 确保路径是目录
         if (!is_dir($dir)) {