text: var importScripts = require("./importscripts.js");
  (() => {
      /* 判断ie11 */
  
      if (
          typeof Promise != "function" ||
          typeof Symbol != "function" ||
          typeof Reflect != "object"
      ) {
          importScripts(
              "https://cdn.bootcdn.net/ajax/libs/babel-polyfill/7.12.1/polyfill.min.js"
          );
      }
  
      if (typeof fetch != "function" || typeof Response != "function") {
          require("./fetch-polyfill.js").default();
      }
  
      if ("function" != typeof URL || "function" != typeof URLSearchParams) {
          require("./url-polyfill.min.js").default();
      }
  
      if ("function" != typeof Event || "function" != typeof CustomEvent) {
          require("./event-polyfill.js").default();
      }
  
      //发现Edge浏览器不支持 new EventTarget！
  
      try {
          new EventTarget();
      } catch (e) {
          window.EventTarget = undefined;
      }
      if ("function" != typeof EventTarget) {
          require("./EventTarget-polyfill.js").default();
      }
      // }
  })();
  /* 
  “URLSearchParams”未定义
  URL.prototype
  undefined
  typeof URL
  "object"
  */
  