nodejs小爬虫代码
var http=require('http');
var cheerio = require('cheerio');
var url='http://www.imooc.com/learn/348';
function filterChapters(html){
var $=cheerio.load(html);
var chapters=$('.chapter');
var courseData = [];
chapters.each(function(item){
var chapter=$(this);
var chapterTitle=chapter.find('strong').text();
var videos=chapter.find('.video').children('li');
var chapterData={
chapterTitle:chapterTitle,
videos:[]
};
videos.each(function(item){
var video=$(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('获取课程失败');
})
