H5 处理服务器返回的 excel 二进制流

sendDown(urls, callback) {
  let that = this;
  var cur = Promise.resolve();
  urls.forEach(function(url) {
    cur = cur.then(function() {
      return that.downFile(url, callback);
    });
  });
  return cur;
},
/**
 *
 * @param {下载接口请求} url
 * @param {*} callback
 */
downFile(url, callback) {
  let filename = '';
  let xhr = '';
  return new Promise(function(resolve, reject) {
    filename = url.substring(url.lastIndexOf('/') + 1).split('?')[0];
    xhr = new XMLHttpRequest();

    xhr.onload = function() {
      resolve(xhr);
    };
    xhr.onerror = reject;
    xhr.open('GET', url);

    try {
      xhr.responseType = 'arraybuffer'; //arraybuffer , blob
    } catch (err) {
      console.error(err);
    }
    xhr.send();
  }).then(xhr => {
    var blob = new Blob([xhr.response], { type: 'application/vnd.ms-excel' });

    if (window.navigator.msSaveOrOpenBlob) {
      window.navigator.msSaveOrOpenBlob(blob, 'data.xlsx');
    } else {
      var downloadUrl = window.URL.createObjectURL(blob);
      let a = document.createElement('a');
      a.href = downloadUrl;
      a.download = 'data.xlsx';
      document.body.appendChild(a);
      a.click();
    }

    return callback && callback(xhr);
  });
},
appendQuery(data) {
  var arr = [];
  for (var i in data) {
    //特殊字符传参产生的问题可以使用encodeURIComponent()进行编码处理
    arr.push(encodeURIComponent(i) + '=' + encodeURIComponent(data[i]));
  }
  return arr.join('&');
},

let URL = that.appendQuery(data.param);
this.sendDown(
    [`${utils.url.curr}/sylla/phr-ui/bonuspm/report/export?${URL}`],
    req => {
      that.loaddingSpinShow = false;
    },
);