python任务25-第一个爬虫和测试

一：

用requests 多次访问百度主页内容,打印返回状态,text内容,计算text属性和cotent属性所返回网页内容的长度

import requests
r=requests.get("http://www.baidu.com")
r.encoding="UTF-8"
for i in range(20):
    print(r.status_code)
    print(r.text)
print(len(r.content))
print(len(r.text))

 二：获取HTML页面内容

from bs4 import BeautifulSoup
import re
soup=BeautifulSoup('''<!DOCTYPE html><head><meta charset="utf-8">
                   <title>菜鸟教程(runoob.com)</title></head><body>
                   <h1>我的第一标题</h1><p id='first'>我的第一段落。</p >
                   </body><table border="1"><tr><td>row 1, cell 1</td>
                   <td>row 1, cell 2</td></tr><tr><td>row 2, cell 1</td>
                   <td>row 2, cell 2</td></tr></table></html>","html.parser''')
print(soup.head,"41") 
print(soup.body) 
print(soup.find_all(id="first")) 
r=soup.text
pat = re.findall(u'[\u1100-\uFFFDh]+?',r)
print(pat)

 

 

三：爬中国大学排名网站（2018）

import csv
import os
import requests
import pandas
from bs4 import BeautifulSoup
allUniv = []
def getHTMLText(url):
    try:
        r = requests.get(url, timeout=30)
        r.raise_for_status()
        r.encoding ='utf-8'
        return r.text
    except:
        return ""
def fillUnivList(soup):
    data = soup.find_all('tr')
    for tr in data:
        ltd = tr.find_all('td')
        if len(ltd)==0:
            continue
        singleUniv = []
        for td in ltd:
            singleUniv.append(td.string)
        allUniv.append(singleUniv)
def writercsv(save_road,num,title):
    if os.path.isfile(save_road):
        with open(save_road,'a',newline='')as f:
            csv_write=csv.writer(f,dialect='excel')
            for i in range(num):
                u=allUniv[i]
                csv_write.writerow(u)
    else:
        with open(save_road,'w',newline='')as f:
            csv_write=csv.writer(f,dialect='excel')
            csv_write.writerow(title)
            for i in range(num):
                u=allUniv[i]
                csv_write.writerow(u)
title=["排名","学校名称","省市","总分","生源质量","培养结果","科研规模",
       "科研质量","顶尖成果","顶尖人才","科技服务","产学研究合作","成果转化"]
save_road="C:\\Users\\疯丫头\\Desktop\\python\\paimimg.csv"
def main():
    url = 'http://www.zuihaodaxue.com/zuihaodaxuepaiming2018.html'
    html = getHTMLText(url)
    soup = BeautifulSoup(html, "html.parser")
    fillUnivList(soup)
    writercsv(save_road,20,title)
main()

 

posted @ 2020-05-13 16:19  猪小叶  阅读(158)  评论(0)  编辑  收藏  举报