爬虫练习（一）爬取鱼c淘贴信息

掏出了以前的小练习；

现在开始，每天复习下以前的爬虫练习，争取发现新的问题和可以优化的地方。

# -*- coding:utf-8 -*-
import requests
import chardet
import csv
from lxml import etree
import re

def get_page(url):
    user_agent = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:61.0) Gecko/20100101 Firefox/61.0'
    header = {'User-Agent':user_agent}
    r = requests.get(url,headers=header)
    r.encoding = chardet.detect(r.content)['encoding']
    page = r.text
    return page

def parse_data(page):
    result = []
    html = etree.HTML(page)
    next_url = html.xpath('//a[@class="nxt"]/@href')
    if len(next_url) > 0:
        next_url = next_url[0]
        print(next_url)
    sites = html.xpath('//*[@class="xld xlda cl"]')
    
    for site in sites:
        title = site.xpath('.//a[@class="xi2"]/text()')[0]
        author = site.xpath('.//p[@class="xg1"]/a/text()')[0]
        theme = site.xpath('.//strong[@class="xi2"]/text()')[0]
        r = site.xpath('./dl/dd[2]/p[2]/text()')[0]
        sub_num,com_num =r.split(',')
        com_num = com_num.strip()
        sub_num = sub_num.strip()
        content = (title,author,theme,sub_num,com_num)
        result.append(content)
    return result,next_url

def main():
    url = 'http://bbs.fishc.org/forum.php?mod=collection'
    results = []
    page = get_page(url)
    result,next_url = parse_data(page)
    results.extend(result)
    q = True
    while q:
        if next_url:
            page = get_page(next_url)
            result,next_url = parse_data(page)
            results.extend(result)
        else:
            q = False
    headers = ['title','author','theme','sub_num','com_num']
    with open(r'taotie.csv','w',encoding = 'utf-8') as f:
        f_csv = csv.writer(f)
        f_csv.writerow(headers)
        try:
            f_csv.writerows(results)
        except UnicodeDecodeError as e:
            print(e)
            
            
if __name__ =="__main__":
    main()