Nodejs小爬虫

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

http.get(url,function(res){
var html=‘‘
res.on(‘data‘,function(data){
html +=data
})
res.on(‘end‘,function(){
console.log(html)
})
}).on(‘error‘,function(){
console.log(‘获取出错‘)
})

/**
 * Created by Amy on 2017/7/13.
 */
var http= require(‘http‘)
var cheerio= require(‘cheerio‘)//先装载这个模块
var url=‘http://www.imooc.com/learn/348‘
function filterChapters(html){
    var $=cheerio.load(html)
    var chapters= $(‘.chapter‘)
    // [{
    //     chapterTitle:‘‘,
    //     videos:[
    //         title:‘‘,
    //          id:‘‘
    //     ]
    // }]
    var courseData=[]
    chapters.each(function(item){
        var chapter=$(this)
        var chapterTitle=chapter.find(‘strong‘).text()
        var videos=chapter.find(‘.video‘).children(‘li‘)
        var chapterData={
            chapterTitle:chapterTitle,
            videos:[]
        }
        videos.each(function(item){
            var video= $(this).find(‘.J-media-item‘)
            var videoTitle=video.text()
            var id = video.attr(‘href‘).split(‘video/‘)[1]

            chapterData.videos.push({
                title:videoTitle,
                id:id
            })
        })
        courseData.push(chapterData)
    })
    return courseData
}
function  printCourseInfo(courseData){
    courseData.forEach(function(item){
        var chapterTitle=item.chapterTitle

        console.log(chapterTitle+‘\n‘)
        item.videos.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(){
        var courseData=  filterChapters(html)
        printCourseInfo(courseData)
    })
}).on(‘error‘,function(){
    console.log(‘获取出错‘)
})