ie下无法识别promise写法 引入cdn

uas-office-web/wxuasapproval/public/index.html

@@ -19,6 +19,7 @@
       work correctly both with client-side routing and a non-root public URL.
       Learn how to configure a non-root public URL by running `npm run build`.
     -->
+    <script src = "https://cdn.polyfill.io/v2/polyfill.min.js"></script>
     <script type="text/javascript">
       function GetQueryString (name) {
         let reg = new RegExp('(^|&)' + name + '=([^&]*)(&|$)')