js文件中引入另一个js文件

function importScript(scriptUrl){
    var script= document.createElement("script");
    script.setAttribute("type", "text/javascript");
    script.setAttribute("src", scriptUrl);
    document.body.appendChild(script);
}


importScript("https://unpkg.com/axios/dist/axios.min.js")

执行importScript 之后不能马上拥有对象，需要等待网络请求

参考 https://blog.csdn.net/qq_42249896/article/details/90769809