今日内容：
一 Selenium剩余部分
二 BeautifulSoup4
一 Selenium剩余部分
1.元素交互操作：
-点击、清除
click
clear
-ActionChains
是一个动作链对象，需要把driver驱动传给它。
动作链对象可以操作一系列设定好的动作行为
-iframe的切换
driver.switch_to.frame('iframeResult')
-执行js代码
execute_script()
from selenium import webdriver
from selenium.webdriver.common.by import By # 按照什么方式查找，By.ID,By.CSS_SELECTOR
from selenium.webdriver.common.keys import Keys # 键盘按键操作
from selenium.webdriver.support import expected_conditions as EC # 和下面WebDriverWait一起用的
from selenium.webdriver.support.wait import WebDriverWait # 等待页面加载某些元素
import time
from selenium.webdriver import ActionChains
driver=webdriver.Chrome(r'F:PYdownloadchromediverchromedriver_win32chromedriver.exe')
# try:
# driver.implicitly_wait(10)#隐式等待
# driver.get('https://www.jd.com/')
#
# #点击、清除
# input=driver.find_element_by_id('key')
# input.send_keys('围城')
#
# #通过class查找搜索按钮
# search=driver.find_element_by_class_name('button')
# search.click()
# time.sleep(3)
#
# input2=driver.find_element_by_id('key')
# input2.clear()#清空输入框
# time.sleep(3)
#
# input2.send_keys('墨菲定律')
# input2.send_keys(Keys.ENTER)
# time.sleep(5)
#
# finally:
# driver.close()
'''
ActionChains
'''
# try:
# driver.implicitly_wait(10)#隐式等待
# driver.get('https://www.runoob.com/try/try.php?filename=jqueryui-api-droppable')
# time.sleep(5)
#
# #遗弃方法
# # driver.switch_to_frame()
# #新方法
# driver.switch_to.frame('iframeResult')
# time.sleep(1)
#
# #起始方块id：draggable
# source=driver.find_element_by_id('draggable')
#
# #目标方块id:droppable
# target=driver.find_element_by_id('droppable')
#
# print(source.size)#大小
# print(source.tag_name)#标签名称
# print(source.text)#文本
# print(source.location)#坐标：X与Y轴
#
# #找到滑动距离
# distance=target.location['x']-source.location['x']
#
# #按住起始滑块
# ActionChains(driver).click_and_hold(source).perform()
#
# #方式二：一点一点移动
# s=0
# while s<distance:
# #获取动作链对象
# #每一次位移s距离
# ActionChains(driver).move_by_offset(xoffset=2,yoffset=0).perform()
# s+=2
#
# time.sleep(0.1)
#
# #松开起始滑块
# ActionChains(driver).release().perform()
#
# time.sleep(10)
# finally:
# driver.close()
'''
js代码
'''
# from selenium import webdriver
# import time
# # driver=webdriver.Chrome()
# try:
# driver.implicitly_wait(10)#隐式等待
# driver.get('https://www.baidu.com/')
#
# driver.execute_script(
# '''
# alert("浙江万里学院")
# '''
# )
# time.sleep(5)
#
#
# finally:
# driver.close()
例如：爬取京东商品信息：
'''
初级版
'''
# import time
# from selenium import webdriver
# from selenium.webdriver.common.by import By # 按照什么方式查找，By.ID,By.CSS_SELECTOR
# from selenium.webdriver.common.keys import Keys
#
# driver=webdriver.Chrome(r'F:PYdownloadchromediverchromedriver_win32chromedriver.exe')
# num=0
# try:
# driver.implicitly_wait(10)
#
# driver.get('https://www.jd.com/')
#
# input_tag=driver.find_element_by_id('key')
# input_tag.send_keys('墨菲定律')
# input_tag.send_keys(Keys.ENTER)
#
# time.sleep(5)
# #下拉滑动5000px
# js_code='''
# window.scrollTo(0,5000)
# '''
# driver.execute_script(js_code)
#
# #等待商品数据加载
# time.sleep(5)
#
# good_list=driver.find_elements_by_class_name('gl-item')
# for good in good_list:
# # print(good)
# #商品名称
# good_name=good.find_element_by_css_selector('.p-name em').text
# # print(good_name)
#
# #商品链接
# good_url=good.find_element_by_css_selector('.p-name a').get_attribute('href')
# # print(good_url)
#
# #商品价格
# good_price=good.find_element_by_class_name('p-price').text
# # print(good_price)
#
# #商品评价
# good_commit=good.find_element_by_class_name('p-commit').text
# # print(good_commit)
#
# good_content = f'''
# 商品名称：{good_name}
# 商品链接：{good_url}
# 商品价格：{good_price}
# 商品评价：{good_commit}
#
# '''
# print(good_content)
#
# with open('jd.txt','a',encoding='utf-8')as f:
# f.write(good_content)
# num+=1
# print('商品信息写入成功！')
#
# #找到下一页，并点击
# next_tag=driver.find_element_by_class_name('pn-next')
# next_tag.clear()
# finally:
# driver.close()
'''
狂暴版
'''
import time
from selenium import webdriver
from selenium.webdriver.common.by import By # 按照什么方式查找，By.ID,By.CSS_SELECTOR
from selenium.webdriver.common.keys import Keys
# driver = webdriver.Chrome(r'F:PYdownloadchromediverchromedriver_win32chromedriver.exe')
def get_good(driver):
num = 0
try:
time.sleep(5)
# 下拉滑动5000px
js_code = '''
window.scrollTo(0,5000)
'''
driver.execute_script(js_code)
# 等待商品数据加载
time.sleep(5)
good_list = driver.find_elements_by_class_name('gl-item')
for good in good_list:
# print(good)
# 商品名称
good_name = good.find_element_by_css_selector('.p-name em').text
# print(good_name)
# 商品链接
good_url = good.find_element_by_css_selector('.p-name a').get_attribute('href')
# print(good_url)
# 商品价格
good_price = good.find_element_by_class_name('p-price').text
# print(good_price)
# 商品评价
good_commit = good.find_element_by_class_name('p-commit').text
# print(good_commit)
good_content = f'''
num:{num}
商品名称：{good_name}
商品链接：{good_url}
商品价格：{good_price}
商品评价：{good_commit}
'''
print(good_content)
with open('jd.txt', 'a', encoding='utf-8')as f:
f.write(good_content)
num += 1
print('商品信息写入成功！')
# 找到下一页，并点击
next_tag = driver.find_element_by_class_name('pn-next')
next_tag.click()
time.sleep(5)
#调用函数本身
get_good(driver)
finally:
driver.close()
if __name__ == '__main__':
driver=webdriver.Chrome(r'F:PYdownloadchromediverchromedriver_win32chromedriver.exe')
try:
driver.implicitly_wait(10)
driver.get('https://www.jd.com/')
input_tag=driver.find_element_by_id('key')
input_tag.send_keys('墨菲定律')
input_tag.send_keys(Keys.ENTER)
#调用获取商品信息函数
get_good(driver)
finally:
driver.close()
二 BeautifulSoup4
BS4
1.什么是BeautifulSoup？
bs4是一个解析库，可以通过某种解析器来帮我们提取想要的数据
2、为什么要使用bs4
因为它可以通过简洁的语言
3.解析器的分类
- lxml
- html.parser
4.安装与使用
- 遍历文档树
- 搜索文档树
补充知识点:
数据格式:
json数据:
{
"name": "tank"
}
XML数据:
<name>tank</name>
HTML:
<html></html>
生成器: yield 值（把值放进生成器中）
def f():
# return 1
yield 1
yield 2
yield 3
g = f()
print(g)
for line in g:
print(line)
bs4解析库的安装与使用
from bs4 import BeautifulSoup
#python自带的解析库
# soup=BeautifulSoup(html_doc,'html.parser')
#调用bs4得到一个soup对象
soup=BeautifulSoup(html_doc,'lxml')
print(soup)
# print(type(soup))
#美化功能
html=soup.prettify()
print(html)
bs4解析库之遍历文档树
html_doc = """
<html><head><title>The Dormouse's story</title></head>
<body>
<p class="sister"><b>$37</b></p>
<p class="story" id="p">Once upon a time there were three little sisters; and their names were
<a href="http://example.com/elsie" class="sister" >Elsie</a>,
<a href="http://example.com/lacie" class="sister" id="link2">Lacie</a> and
<a href="http://example.com/tillie" class="sister" id="link3">Tillie</a>;
and they lived at the bottom of a well.</p>
<p class="story">...</p>
"""
from bs4 import BeautifulSoup
soup=BeautifulSoup(html_doc,'lxml')
# print(soup)
# print(type(soup))
# 遍历文档树
# 1、直接使用
# print(soup.html)
# print(type(soup.html))
print(soup.a)
print(soup.p)
# 2、获取标签的名称
# print(soup.a.name)
#3、获取标签的属性 *****
print(soup.a.attrs) #获取a标签中所有属性
print(soup.a.attrs['href'])
#4、获取标签的文本内容 *****
print(soup.p.text)
#5、嵌套选择
print(soup.html.body.p)
#6、子节点、子孙节点
print(soup.p.children)#返回迭代器对象
print(list(soup.p.children))
#7、父节点、祖先节点
print(soup.b.parent)
print(soup.b.parents)
print(list(soup.p.parents))
#8、兄弟节点 (sibling:兄弟姐妹)
print(soup.a)
#获取下一个兄弟结点
print(soup.a.next.sibling)
#获取下一个的所有兄弟节点，返回的是一个生成器
print(soup.a.next_siblings)
print(list(soup.a.next_siblings))
#获取上一个兄弟节点
print(soup.a.previous_sibling)
#获取上一个的所有兄弟节点，返回的是一个生成器
print(list(soup.a.previous_siblings))
bs4解析库之搜索文档树
'''
find :找第一个
find_all:找所有
标签查找与属性查找:
标签:
- 字符串过滤器 字符串全局匹配
name 标签名
attrs 属性查找匹配
text 文本匹配
- 正则过滤器
re模块匹配
- 列表过滤器
列表内的数据匹配
- bool过滤器
True匹配
- 方法过滤器
用于一些要的属性以及不需要的属性查找。
属性:
- class_
- id
'''
html_doc = """
<html><head><title>The Dormouse's story</title></head><body><p class="sister"><b>$37</b></p>
<p class="story" id="p">Once upon a time there were three little sisters; and their names were<a href="http://example.com/elsie" class="sister" >Elsie</a>
<a href="http://example.com/lacie" class="sister" id="link2">Lacie</a> and<a href="http://example.com/tillie" class="sister" id="link3">Tillie</a>
and they lived at the bottom of a well.</p><p class="story">...</p>
"""
from bs4 import BeautifulSoup
soup=BeautifulSoup(html_doc,'lxml')
# name 标签名
# attrs 属性查找匹配
# text 文本匹配
'''
字符串过滤器
'''
p=soup.find(name='p')
p_s=soup.find_all(name='p')
print(p)
print(p_s)
#name+attrs
p=soup.find(name='p',attrs={"id":"p"})
print(p)
#name+text
tag=soup.find(name='title',text="The Dormouse's story")
print(tag)
#name+attrs+text
tag=soup.find(name='a',attrs={"class":"sister"},text="Elsie")
print(tag)
'''
正则过滤器
re模块匹配
'''
import re
#name
#根据re模块匹配带有a的节点
a=soup.find(name=re.compile('a'))
print(a)
a_s=soup.find_all(name=re.compile('a'))
print(a_s)
#attrs
a=soup.find(attrs={"id":re.compile('link')})
print(a)
#-列表过滤器
#列表内的数据匹配
print(soup.find(name=['a','p','html',re.compile('a')]))
print(soup.find_all(name=['a','p','html',re.compile('a')]))
#-bool过滤器
#True匹配
print(soup.find(name=True,attrs={"id":True}))
#-方法过滤器
#用于一些要的属性以及不需要的属性查找
def have_id_not_class(tag):
#print(tag.name)
if tag.name=='p' and tag.has_attr("id") and not tag.has_attr("class"):
return tag
#print(soup.find_all(name=函数对象))
print(soup.find_all(name=have_id_not_class()))
#补充知识点：
a=soup.find(id='link2')
print(a)
#class
p=soup.find(class_='sister')
print(p)