koa-router中间件

1 .安装koa-router中间件

  npm  install --save koa-router

2 .最基本的koa-router的写法

 const Koa= require ('koa')
const Router = require ('koa-router')

const app= new Koa()
const router =new Router()

router.get('/',(ctx,next)=>{
                 ctx.body='hellow world'
            })
      .get('/my',(ctx ,next)=>{
                 ctx.body='this. is my'
            })

      app .use(router.routes())
          .use(router.allowedMethods())
app.listen(3000,()=>{
      console.log('starting at port 3000');
  });

3 .层级

const Koa = require('koa');
const app = new Koa();
const Router = require('koa-router');

//子路由
let home = new Router();
home.get('/jspang',async(ctx)=>{
    ctx.body="Home JSPang";
}).get('/todo',async(ctx)=>{
    ctx.body ='Home ToDo';
})

//子路由
let page = new Router();
page.get('/jspang',async(ctx)=>{
    ctx.body="Page JSPang";
}).get('/todo',async(ctx)=>{
    ctx.body ='Page ToDo';
})

//总路由装载所有子路由
let router = new Router();
router.use('/home',home.routes(),home.allowedMethods());
router.use('/page',page.routes(),page.allowedMethods());

//加载路由中间件
app.use(router.routes()).use(router.allowedMethods());

app.listen(3000,()=>{
    console.log('[demo] server is starting at port 3000');
});