nodejs 之 小爬虫

var http = require(‘http‘) var url = ‘http://www.imooc.com/learn/348‘ 
http.get(url,function(res){ 
　　var html = ‘‘
    //有data触发时
    res.on(‘data‘,function(data){
        html += data
    })
    res.on(‘end‘,function(){
        console.log(html)
    })
//出现异常时
}).on(‘error‘,function(){
    console.log(‘获取出错‘)
})

var server = http.createServer(function(req,res){
        res.writeHead(200,{‘Content-Type‘:‘text/plain‘})
        res.end();
    })
server.listen(2017)

var http = require(‘http‘)
var cheerio = require(‘cheerio‘)
var url = ‘http://www.imooc.com/learn/348‘

//过滤页面，获取到列表的名称与id等信息  与javascript方法一致
function filterChapters(html){
    var $ = cheerio.load(html)
    // console.log($)
    var chapters = $(‘.chapter‘)

    var courseData = []
    chapters.each(function (item) {
        var chapter = $(this)
        var chapterTitle = chapter.find(‘strong‘).text()
        var videos = chapter.find(‘.video‘).children(‘li‘)
        var chapterData = {
            chapterTitle:chapterTitle,
            video:[]
        }
        // console.log(videos + ‘24‘)
        videos.each(function(item){
            // var video = $(this).find(‘.studyvideo‘)
            var videoTitle = $(this).text()
            var id = $(this).attr("data-media-id")

            chapterData.video.push({
                title:videoTitle,
                id:id
            })
        })
        courseData.push(chapterData)
    })
    return courseData
}
//将获取到的信息打印出来
function printCourseInfo(courseData) {
    courseData.forEach(function(item){
        var chapterTitle = item.chapterTitle
        item.video.forEach(function(video){
            console.log(‘【‘ +video.id+‘】‘ +video.title +‘\n‘)
        })
    })
}
http.get(url,function(res){
    var html = ‘‘
    res.on(‘data‘,function(data){
        html += data
    })
    res.on(‘end‘,function(){
        //过滤页面信息
        // console.log(html)
        var courseData = filterChapters(html)
        printCourseInfo(courseData)
    })
}).on(‘error‘,function(){
    console.log(‘获取出错‘)
})

var server = http.createServer(function(req,res){
        res.writeHead(200,{‘Content-Type‘:‘text/plain‘})
        res.end();
    })
server.listen(1337)