# 7-Http Client

這程式主要的目標是，要抓網頁的原始碼，也就是 html 檔案下來，顯示到 console or terminal 中。也是一個我不看解答就不知道怎麼開始的題目 ...

## 官網的答案

其實官網的答案我看不太懂，尤其是最後一句話 `.on( 'error', console.error)`。為什麼 js 有這麼多違反直覺的東西啊(倒地)

所以我決定，投機取巧，先看別人的改良版本

```javascript
// 發起 http request 和 response
// 但好像不用建立 server

var http = require('http')

http.get(process.argv[2], function (response) {

    response.setEncoding( 'utf8' )
    response.on( 'data' , console.log  )
    response.on( 'error', console.error)

}).on( 'error', console.error)
```

## 別人的改良版本

他同時可以讀取 http 和 https 協定的網頁，然後字串的部份他用 `data.toString()` 來轉換，取代官方的`response.setEncoding( 'utf8' )`。

老實說，我都看不懂啊 orz

```javascript
// 可以讀取 http 和 https 的網頁

var http = require('http')
var https = require('https')

var url = process.argv[2]
var prefix = url.substring(0,8)

if (prefix === 'https://'){
  https.get(url, function (response) {

    response.setEncoding( 'utf8' )
    response.on( 'data', console.log )

   // response.on('data', function (data) {
   //   console.log(data.toString());
   // })
  })
} else {
  http.get(url, function (response) {
    response.on('data', function (data) {
      console.log(data.toString());
    })
  })
}
```

stream, 'data'

* [Stream | Node.js v7.2.1 Documentation](https://nodejs.org/api/stream.html#stream_event_data)

http.get()

* [HTTP | Node.js v7.2.1 Documentation](https://nodejs.org/api/http.html#http_http_get_options_callback)

Event, emitter.on

* [Events | Node.js v7.2.1 Documentation](https://nodejs.org/api/events.html#events_emitter_on_eventname_listener)
* [Is the 'on' method in this node.js code a JavaScript method or a node method? - Stack Overflow](http://stackoverflow.com/questions/8187507/is-the-on-method-in-this-node-js-code-a-javascript-method-or-a-node-method)
* [javascript - In node.js "request.on" what is it this ".on" - Stack Overflow](http://stackoverflow.com/questions/12892717/in-node-js-request-on-what-is-it-this-on)


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