1. 确定 URL
from urllib import request
import re
#定义url
page=50
url="https://tieba.baidu.com/f?kw=%E6%AE%B5%E5%AD%90&ie=utf-8&pn="+str(page)
2.添加headers并抓取页面代码
try:
    #定义请求头
    headrs={"User-Agent":" Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36"}
    #定义请求，传入请求头
    req=request.Request(url,headers=headrs)
    #打开网页
    resp=request.urlopen(req)
    #打印响应码，解码
    # print(resp.read().decode('utf-8'))
   
3. 使用正则表达式提取某一页的所有段子

 content=resp.read().decode('utf-8')
    #定义正则表达式
    #<a rel="noopener" 具体的东西
    #.*? 匹配没用的数据
    #(.*?)匹配有用数据分组
    #\s 空格
    pattern=re.compile(r'<a rel="noopener".*?title=(.*?)\s.*?>(.*?)</a>')
    #匹配html
    items=re.findall(pattern,content)
    #打印解析的内容
    for i in items:
        print("标题:"+i[0]+" 内容:"+i[1])
 
except request.URLError as e:
    #打印响应码
    if hasattr(e,'code'):
        print(e.code)
    #打印异常原因
    if hasattr(e,'reason'):
        print(e.reason)
面向对象模式
from urllib import request
import re
 
class tieba:
    #初始化
    def __init__(self):
        # 定义url
        self.url="https://tieba.baidu.com/f?kw=%E6%AE%B5%E5%AD%90&ie=utf-8&pn="
        # 定义请求头
        self.headrs={"User-Agent":" Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36"}
        #列表，存储解析后的结果
        self.stories=[]
    #下载页面
    def getPage(self,page_number):
        try:
            # 定义请求，传入请求头
            req=request.Request(self.url+str(page_number),headers=self.headrs)
            # 打开网页
            resp=request.urlopen(req)
            # 打印响应码，解码
            content=resp.read().decode("utf-8")
            return content
        except request.URLError as e:
            # 打印响应码
            if hasattr(e, 'code'):
                print(e.code)
            # 打印异常原因
            if hasattr(e, 'reason'):
                print(e.reason)
    #解析页面
    def rexgPage(self,content):
        # 定义正则表达式
        # <a rel="noopener" 具体的东西
        # .*? 匹配没用的数据
        # (.*?)匹配有用数据分组
        # \s 空格
        pattern = re.compile(r'<a rel="noopener".*?title=(.*?)\s.*?>(.*?)</a>')
        # 匹配html
        items = re.findall(pattern, content)
        # 添加解析的内容
        for i in items:
            # print("标题:" + i[0] + " 内容:" + i[1])
            self.stories.append("标题:" + i[0] + " 内容:" + i[1])
    #显示解析的内容
    def getContent(self):
        for i in self.stories:
            print(i)
 
 
#创建对象
c=tieba()
#调用方法
c.rexgPage(c.getPage(100))
c.getContent()