update

app/controller/Upload.php

@@ -14,7 +14,7 @@ class Upload
             return show("请选择图片！");
         }
         $file = $GLOBALS['data']['file'];
-        $dir = env('upload_directory');
+        $dir = env('UPLOAD_DIRECTORY');
         if(!is_dir($dir)){
             mkdir($dir, 0777, true);
         }