Ant Design of Vue中对a-upload组件封装，1.实现上传功能2.实现下载功能3.单个文件上传不能超过1024m4.显示上传的文件列表5.文件列表右侧有删除按钮，可以实现删除功能6.用ts语法实现前面功能

以下是对a-upload组件的封装，实现了上传、下载、文件列表展示、删除等功能，并使用了TypeScript语法：

<template>
  <div>
    <a-upload
      :action="uploadUrl"
      :before-upload="beforeUpload"
      :on-success="onUploadSuccess"
      :on-error="onUploadError"
      :on-remove="onRemove"
    >
      <a-button icon="upload">上传文件</a-button>
    </a-upload>
    <a-table :columns="columns" :data-source="fileList" row-key="uid"></a-table>
  </div>
</template>

<script lang="ts">
import { Component, Vue } from 'vue-property-decorator';
import { Upload, Button, Table, Icon, Modal, message } from 'ant-design-vue';
import { AxiosResponse } from 'axios';

interface FileItem {
  uid: string;
  name: string;
  status: 'uploading' | 'done' | 'error' | 'removed';
  url?: string;
}

@Component({
  components: {
    'a-upload': Upload,
    'a-button': Button,
    'a-table': Table,
    'a-icon': Icon,
    'a-modal': Modal,
  },
})
export default class MyUpload extends Vue {
  private fileList: FileItem[] = [];

  private uploadUrl = '/api/upload';

  private columns = [
    {
      title: '文件名',
      dataIndex: 'name',
    },
    {
      title: '状态',
      dataIndex: 'status',
    },
    {
      title: '操作',
      scopedSlots: { customRender: 'operation' },
    },
  ];

  private beforeUpload(file: File) {
    const isLt1G = file.size / 1024 / 1024 < 1024;
    if (!isLt1G) {
      message.error('不能上传超过1G的文件！');
    }
    return isLt1G;
  }

  private onUploadSuccess(response: AxiosResponse, file: FileItem) {
    file.status = 'done';
    file.url = response.data.url;
    message.success('上传成功！');
  }

  private onUploadError(error: Error, file: FileItem) {
    file.status = 'error';
    message.error('上传失败！');
  }

  private onRemove(file: FileItem) {
    Modal.confirm({
      title: '确定删除该文件吗？',
      onOk: () => {
        const index = this.fileList.findIndex((item) => item.uid === file.uid);
        this.fileList.splice(index, 1);
        message.success('删除成功！');
      },
      onCancel: () => {},
    });
  }

  private downloadFile(url: string) {
    const a = document.createElement('a');
    a.href = url;
    a.target = '_blank';
    a.download = url.split('/').pop() || '';
    a.click();
  }

  private getOperationSlot(record: FileItem) {
    if (record.status === 'done' && record.url) {
      return (
        <div>
          <a-button type="link" onClick={() => this.downloadFile(record.url || '')}>
            下载
          </a-button>
          <a-button type="link" onClick={() => this.onRemove(record)}>
            删除
          </a-button>
        </div>
      );
    }
    if (record.status === 'uploading') {
      return <a-icon type="loading" />;
    }
    return null;
  }
}
</script>

在这个组件中，我们使用了Ant Design of Vue提供的Upload、Button、Table、Icon、Modal和Message等组件，实现了上传、下载、文件列表展示、删除等功能。其中，beforeUpload方法用于限制上传文件大小，onUploadSuccess和onUploadError方法用于处理上传成功和失败的情况，onRemove方法用于删除文件，downloadFile方法用于下载文件，getOperationSlot方法用于自定义操作列的内容。