text: function get() {
    var xhr = new XMLHttpRequest();
    xhr.open("GET", "https://g.alicdn.com/alilog/mlog/aplus_v2.js", true);
    xhr.onreadystatechange = (x) => {
      if (xhr.readyState === 4) {
        if (xhr.status >= 200 && xhr.status < 300) {
          let string = request.responseText;
          let obj = JSON.parse(string);
          console.log(obj);
        }
      }
    };
    xhr.send(null);
  }
  get();
  
  function ajax(options) {
    let url = options.url;
    let method = options.method;
    let body = options.body;
    let success = options.success;
    let fail = options.fail;
  
    let request = new XMLHttpRequest();
    request.open(method, url);
    request.onreadystatechange = () => {
      if (request.readyState === 4) {
        if (request.status >= 200 && request.status < 300) {
          success.call(undefined, request.responseText);
        } else if (request.status >= 400) {
          fail.call(undefined, request);
        }
      }
    };
    request.send(body);
  }
  