diff --git a/library/think/Request.php b/library/think/Request.php
index f4854757..d4f96a75 100644
--- a/library/think/Request.php
+++ b/library/think/Request.php
@@ -886,7 +886,7 @@ class Request
                 return $array[$name];
             }
         }
-        return null;
+        return;
     }
 
     /**