···
$ npm i multer --save

/routes/index.js 路由中：

var express = require('express');
var router = express.Router();

var path = require('path');
var multer = require('multer');
var fs = require('fs');
var upload = multer({ dest: path.join(__dirname, '../public/upload/') });

// 注意：1、'upload_file' 对应于 form 表单中的 name 属性值。
// 2、代码 执行完 upload.single('upload_file') 的时候，文件就已经上传了，但是没有后缀名，得手动改一下
router.post('/upload_bgImg', upload.single('upload_file'), function(req, res) {
var temp_path = req.file.path;
var ext = '.' + req.file.originalname.split('.')[1];
var target_path = req.file.path + ext;
var _filename = req.file.filename + ext;
var filePath = '/upload/' + _filename;
console.log("Uploading: " + _filename);
fs.rename(temp_path, target_path, function(err,data) {
cb(null, { file_path: filePath });
});
});
···