const express = require('express'); const app = express(); const bodyParser = require('body-parser'); //拦截所有请求 //extends:true 方法内部使用第三方模块请求的参数 app.use(fn({ a: 1 })); function fn(obj) { return function(req, res, next) { if (obj.a == 1) { console.log(req.url); } else { console.log(req.method) } next(); } } app.get('/', (req, res) => { res.send('ok'); }) app.listen(3000); console.log('服务器启动成功');