element-ui,Upload 上传组件,单按钮图片上传

<el-upload
  class="upload-demo"
  action="https://jsonplaceholder.typicode.com/posts/"
  :show-file-list="false"
  accept="image/*"
  :on-success="
     (response, file, fileList) => {
        uploadSuccess(response, file, fileList, '自定义参数');
     }
  "
  >
  <el-button size="small" type="primary">点击上传</el-button>
</el-upload>
methods:{
  uploadSuccess(response, file, fileList, item) {
   console.log("on-success");
   console.log(response);
   console.log(file);
   console.log(fileList);
  },
}