diff --git a/backend/logic/file/FileManager.php b/backend/logic/file/FileManager.php
index da311a8..d8e054c 100644
--- a/backend/logic/file/FileManager.php
+++ b/backend/logic/file/FileManager.php
@@ -25,11 +25,11 @@ class FileManager
 
     /**
      * @param $array
-     * @param $value
-     * @return int
-     * 查看$extension数组中是否存在文件类型，不存在则返回-1
+     * @param $keyword
+     * @return bool|int|string
+     * 根据文件拓展名在$extension中查找对应的文件类型，若不存在则返回false
      */
-    public function searchType($array, $keyword, $key=-1){
+    public function searchType($array, $keyword){
         foreach($array as $key => $value){
             foreach ($value as $k => $v) {
                 if($v == $keyword){