vant上传图片

<van-uploader :after-read="onRead">
 <img :src="dataT.avatar" ref="usersImg">
</van-uploader>

dataT: {
        avatar: "",
      }

// 上传头像
    onRead(file) {
      let params = new FormData(); //创建form对象
      params.append("file", file.file); //通过append向form对象添加数据//第一个参数字符串可以填任意命名，第二个根据对象属性来找到file
      let config = {
        headers: { //添加请求头
          Authorization:
            "Bearer " + window.localStorage.getItem("managementToken"),
          "Content-Type": "multipart/form-data"
        }
      };
     let url = "";
      axios.post(url, params, config).then(res => {
          console.log(res);
        }).catch(err => {
          console.log(err)
        });
    },