Express+React+Antd实现上传功能(前端和后端)

npx create-react-app myapp

npm install antd --save

import React, { useState } from 'react';
import { PlusOutlined } from '@ant-design/icons';
import { Image, Upload } from 'antd';
const getBase64 = (file) =>
  new Promise((resolve, reject) => {
    const reader = new FileReader();
    reader.readAsDataURL(file);
    reader.onload = () => resolve(reader.result);
    reader.onerror = (error) => reject(error);
  });
const MyUpload = () => {
  const [previewOpen, setPreviewOpen] = useState(false);
  const [previewImage, setPreviewImage] = useState('');
  const [fileList, setFileList] = useState([
    {
      uid: '-1',
      name: 'image.png',
      status: 'done',
      url: 'https://zos.alipayobjects.com/rmsportal/jkjgkEfvpUPVyRjUImniVslZfWPnJuuZ.png',
    },
    {
      uid: '-2',
      name: 'image.png',
      status: 'done',
      url: 'https://zos.alipayobjects.com/rmsportal/jkjgkEfvpUPVyRjUImniVslZfWPnJuuZ.png',
    },
    {
      uid: '-3',
      name: 'image.png',
      status: 'done',
      url: 'https://zos.alipayobjects.com/rmsportal/jkjgkEfvpUPVyRjUImniVslZfWPnJuuZ.png',
    },
  ]);
  const handlePreview = async (file) => {
    if (!file.url && !file.preview) {
      file.preview = await getBase64(file.originFileObj);
    }
    setPreviewImage(file.url || file.preview);
    setPreviewOpen(true);
  };
  const handleChange = ({ fileList: newFileList }) => setFileList(newFileList);
  const uploadButton = (
    <button
      style={{
        border: 0,
        background: 'none',
      }}
      type="button"
    >
      <PlusOutlined />
      <div
        style={{
          marginTop: 8,
        }}
      >
        上传图片
      </div>
    </button>
  );
  return (
    <>
      <Upload
        action=""
        listType="picture-card"
        fileList={fileList}
        onPreview={handlePreview}
        onChange={handleChange}
      >
        {fileList.length >= 8 ? null : uploadButton}
      </Upload>
      {previewImage && (
        <Image
          wrapperStyle={{
            display: 'none',
          }}
          preview={{
            visible: previewOpen,
            onVisibleChange: (visible) => setPreviewOpen(visible),
            afterOpenChange: (visible) => !visible && setPreviewImage(''),
          }}
          src={previewImage}
        />
      )}
    </>
  );
};
export default MyUpload;

npm init

npm install express --save

npx express-generator  或者 npm install express-generator

npm install multer

import express from 'express'
import multer from 'multer'
const app = express()
// 设置存储配置
const storage = multer.diskStorage({
  destination: function (req, file, cb) {
    cb(null, 'uploads/')
  },
  filename: function (req, file, cb) {
    cb(null, file.fieldname + '-' + Date.now() + file.originalname)
  }
})
const upload = multer({ storage: storage });
// 解析post请求body参数
app.use(express.urlencoded({extended: false }))
app.use(express.json())
// 托管静态文件
app.use('/uploads', express.static('uploads'))
// 设置跨域
app.all('*', function (req, res, next) {
  res.header('Access-Control-Allow-Origin', '*');
  res.header('Access-Control-Allow-Headers', 'Content-Type');
  res.header('Access-Control-Allow-Methods', '*');
  res.header('Content-Type', 'application/json;charset=utf-8');
  next();
});
// 处理上传的图片
app.post('/upload', upload.single('image'), (req, res) => {
  const file = req.file;
  console.log(file);
  if (!file) {
    return res.status(400).send('No file uploaded.');
  }
  res.json('File uploaded successfully.');
});
import routerLogin from './router/login.js'
import routerList from './router/list.js';
app.use('/api', routerLogin)
app.use('/api', routerList)
const port = 4000
app.listen(port, () => {
  console.log(`端口运行于http://127.0.0.1:${port}`);
})