this.source = axios.CancelToken.source();
          axios({
            method: 'post',
            url: baseUrl + url,
            headers: {
              'Content-Type': 'multipart/form-data;'
            },
            data: formData,
            cancelToken: this.source.token,//监听取消上传接口
            onUploadProgress(e) {//监听上传进度
              if (e.lengthComputable) {
                let rate = Math.round((e.loaded * 100) / e.total);
                if (rate < 100) {
                  that.percentage = rate
                }
              }
            }
          }).then(response => {
              //上传成功，进度设为100%
              that.percentage = 100
            }).catch(error => {
              if (error.message != 'cancel') {
                //取消上传处理
              }
            });

//取消方法
          if (this.source) {
            this.source.cancel('cancel');
          }