vue动态加载javascript

const Utils = {
   /**
   * 加载js
   * @param src
   */
  loadScript(src) {
    return new Promise((resolve, reject) => {
      const script = document.createElement("script"),
        head = document.getElementsByTagName("head")[0];
      script.type = "text/javascript";
      script.src = src;
      if (script.addEventListener) {
        script.addEventListener(
          "load",
          function () {
            resolve();
          },
          false
        );
      } else if (script.attachEvent) {
        script.attachEvent("onreadystatechange", function () {
          const target = window.event.srcElement;
          if (target.readyState == "loaded") {
            resolve();
          }
        });
      }
      head.appendChild(script);
    });
  },
  /**
   * 加载多个js
   * @param src
   * @param callback
   */
  loadMoreScript(src) {
    if (_.isArray(src)) {
      const list = [];
      src.forEach((itemUrl) => {
        list.push(Utils.loadScript(itemUrl));
      });
      return Promise.all(list);
    } else {
      return Utils.loadScript(src);
    }
  },
}