例子
const Koa = require('koa')
const app = new Koa()
app.use( async ( ctx ) => {
let url = ctx.request.url
ctx.body = url
})
app.listen(9999)
现在你访问 (http://localhost:3000/hello/world)页面会输出hello/world,现在也就是说请求中url就是当前的访问的路径名称,可以根据ctx.request.url通过一定的判断或者正在就可以定制出所需要的路由
const Koa = require("koa")
const fs = require("fs")
const app = new Koa()
/**
* 用Promise封装异步读取文件方法
* @param {string} page html文件名称
* @return {promise}
*/
function render( page ) {
return new Promise(( resolve, reject ) => {
let viewUrl = `./view/${page}`
fs.readFile(viewUrl, "binary", ( err, data ) => {
if ( err ) {
reject( err )
} else {
resolve( data )
}
})
})
}
/**
* 根据URL获取HTML内容
* @param {string} url koa2上下文的url,ctx.url
* @return {string} 获取HTML文件内容
*/
async function route( url ) {
let view = '404.html'
switch ( url ) {
case '/':
view = 'index.html'
break
case '/index':
view = 'index.html'
break
case '/todo':
view = 'todo.html'
break
case '/404':
view = '404.html'
break
default:
break
}
let html = await render( view )
return html
}
app.use( async ( ctx ) => {
let url = ctx.request.url
let html = await route( url )
ctx.body = html
})
app.listen(9999)
console.log("[demo] start-quick is starting at port 9999")
执行node -harmony index.js
就可以看到输出页面
index.html