Environment
Node 8.0.0
koa 2.2.0
koa-router 7.1.1

const router = require('koa-router')() router.prefix('/logs/mobile') router.get('/:platform', function(cxt, next) { console.log('params', this.params); cxt.body = { error: 'test'} }) module.exports = router

The code is as shown above, and then accesshttp://127.0.0.1:9901/logs/mobile/iosand successfully obtain the return value of the body,
butthis.paramsisundefined