上传文件到七牛云并限制并发数量

//并发控制
arr是文件上传的fileList数组 


const limitLoad = (arr, load, limit) => {
  const sequence = [].concat(arr);
  let promise = [];
  promise = sequence.splice(0, limit).map((url, index) => {
    return load(url).then(() => {
      return index;
    });
  });
  let p = Promise.race(promise);
  // for循环给p赋值相当于.then().then()链式调用
  for (let i = 0; i < sequence.length; i++) {
    p = p.then((res) => {
      promise[res] = load(sequence[i]).then(() => {
        return res;
      });
      return Promise.race(promise);
    });
  }
};

const load = (file) => {
  return new Promise((reslove, reject) => {
    updateFileList(file, reslove);//调用七牛的上传
  });
};

//上传文件
const updateFileList = async (file, resolve) => {
    //获取视频或者音频时长
    var fileurl = URL.createObjectURL(file);
    var audioElement = new Audio(fileurl);
    audioElement.addEventListener("loadedmetadata", function (_event) {
      file.duration = parseInt(audioElement.duration);
    });
    const config = {
      useCdnDomain: true,
      region: qiniu.region.z2, // 根据地区不同，官网有不同的配置
    };
    const key =
      "uploads/" +
      ("video/mp4".includes(file.name.split(".")[1]) ? "video" : "image") +
      "/" +
      moment().format("YYYY-MM-DD") +
      "/" +
      Math.floor(Math.random() * 99999) +
      "/" +
      file.name;
    const observable = await qiniu.upload(
      file,
      key, //文件名
      UserQiniu.token,
      config
    );
    // 上传视频文件
    observable.subscribe({
      next(res) {
        //上传进度
        ruleForm.fileList.forEach((item) => {
          if (item.raw.uid == file.uid) {
            item.percentage = res.total.percent;
          }
        });
      },
      error(err) {
      },
      complete(res) {
      '''
      '''
        resolve();
      },
    });

上传文件的几个回调根据自己的情况设置条件即可 参考意义不大