自动化测试工具，支持多种浏览器。爬虫中主要用来解决javaScrapt渲染的问题。
安装：pip install selenium,brew install chromedriver
基本使用
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.support.wait import WebDriverWait
browser = webdriver.Chrome()
try:
browser.get('http://www.baidu.com')
input = browser.find_element_by_id('kw')
input.send_keys('python')
input.send_keys(Keys.ENTER)
wait = WebDriverWait(browser, 10)
wait.until(EC.presence_of_element_located((By.ID, 'content_left')))
print(browser.current_url)
print(browser.get_cookies())
print(browser.page_source)
finally:
browser.close()
声明浏览器对象
from selenium import webdriver
browser = webdriver.Chrome()
browser = webdriver.Firefox()
browser = webdriver.Edge()
browser = webdriver.PhantomJS()
browser = webdriver.Safari()
访问页面
from selenium import webdriver
browser = webdriver.Chrome()
browser.get('http://www.taobao.com')
print(browser.page_source)
browser.close()
单个元素
from selenium import webdriver
browser = webdriver.Chrome()
browser.get('http://www.taobao.com')
input_first = browser.find_element_by_id('q')
input_second = browser.find_element_by_css_selector('#q')
input_third = browser.find_element_by_xpath('//*[@id="q"]')
print(input_first, input_second, input_third)
browser.close()
find_element_by_name
find_element_by_xpath
find_element_by_link_text
find_element_by_partial_link_text
find_element_by_tag_name
find_element_by_class_name
find_element_by_css_selector
多个元素
from selenium import webdriver
from selenium.webdriver.common.by import By
browser = webdriver.Chrome()
browser.get('http://www.taobao.com')
lis1 = browser.find_elements_by_css_selector('.service-bd li')
lis2 = browser.find_elements(By.CSS_SELECTOR, '.service-bd li')
print(lis1, lis2)
browser.close()
find_elements_by_name
find_elements_by_xpath
find_elements_by_link_text
find_elements_by_partial_link_text
find_elements_by_tag_name
find_elements_by_class_name
find_elements_by_css_selector
元素交互操作
from selenium import webdriver
import time
from selenium.webdriver.common.by import By
browser = webdriver.Chrome()
browser.get('http://www.taobao.com')
input = browser.find_element_by_id('q')#找到id为q的input文本框
input.send_keys('iphone')#文本框输入iphone搜索
time.sleep(1)
input.clear()#把文本框清空
input.send_keys('ipad')
button = browser.find_element_by_class_name('btn-search')
button.click()#模拟点击搜索按钮
#现在有登陆验证了。。。
更多内容查看https://selenium-python-zh.readthedocs.io/en/latest/index.html
元素交互动作
from selenium import webdriver
from selenium.webdriver import ActionChains
browser = webdriver.Chrome()
url = 'http://www.runoob.com/try/try.php?filename=jqueryui-api-droppable'
browser.get(url)
browser.switch_to.frame('iframeResult')
source = browser.find_element_by_css_selector('#draggable')
target = browser.find_element_by_css_selector('#droppable')
actions = ActionChains(browser)
actions.drag_and_drop(source, target)
actions.perform()
执行javascrapt
from selenium import webdriver
browser = webdriver.Chrome()
browser.get('https://www.zhihu.com/explore')
browser.execute_script('window.scrollTo(0,document.body.scrollHeight)')
browser.execute_script('alert("To Botton")')
获取属性值
from selenium import webdriver
browser = webdriver.Chrome()
browser.get('https://www.zhihu.com/explore')
logo = browser.find_element_by_id('zh-top-link-logo')
print(logo)
print(logo.get_attribute('class'))
获取文本值
from selenium import webdriver
browser = webdriver.Chrome()
browser.get('https://www.zhihu.com/explore')
input = browser.find_element_by_class_name('zu-top-add-question')
print(input.text)
获取ID，位置，标签名，大小
from selenium import webdriver
browser = webdriver.Chrome()
browser.get('https://www.zhihu.com/explore')
input = browser.find_element_by_class_name('zu-top-add-question')
print(input.text)
print(input.location)
print(input.tag_name)
print(input.size)
Frame
import time
from selenium import webdriver
from selenium.common.exceptions import NoSuchElementException
browser = webdriver.Chrome()
url = 'http://www.runoob.com/try/try.php?filename=jqueryui-api-droppable'
browser.get(url)
browser.switch_to.frame('iframeResult')
source = browser.find_element_by_css_selector('#draggable')
print(source)
try:
logo = browser.find_element_by_class_name('logo')
except NoSuchElementException:
print('No logo')
browser.switch_to.parent_frame()
logo = browser.find_element_by_class_name('logo')
print(logo)
print(logo.text)
等待
隐式等待
from selenium import webdriver
browser = webdriver.Chrome()
browser.implicitly_wait(10)
browser.get('https://www.zhihu.com/explore')
input = browser.find_element_by_class_name('zu-top-add-question')
print(input)
显示等待
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
browser = webdriver.Chrome()
browser.get('https://www.taobao.com/')
wait = WebDriverWait(browser,10)
input = wait.until(EC.presence_of_element_located((By.ID,'q')))
button = wait.until(EC.element_to_be_clickable((By.CSS_SELECTOR,'btn-search')))
print(input,button)
title_is 标题是某内容
title_contains 标题包含某内容
presence_of_element_located 元素加载出，传入定位元组，如（By.ID, 'p'）
visibility_of_element_located 元素可见，传入定位元组
visibility_of 可见，传入元素对象
presence_of_all_element_located 所有元素加载出
text_to_be_present_in_element 某个元素文本包含某文字
text_to_be_present_in_element_value 某个元素值包含某文字
frame_to_be_available_and_switch_to_it frame加载并切换
invisibility_of_element_located 元素不可见
element_to_be_clickable 元素可点击
staieness_of 判断一个元素是否仍在DOM.可判断页面是否已经刷新
element_to_be_selected 元素可选择，传元素对象
element_located_to_be_selected 元素可选择，传入定位元素
element_selection_state_to_be 传入元素对象以及状态，相等返回True, 否则返回false
element_located_selection_state_to_be 传入定位元组以及状态，相等返回True,否则返回false
alert_is_pressent 是否出现alert
前进后退
from selenium import webdriver
import time
browser = webdriver.Chrome()
browser.get('https://www.zhihu.com/explore')
browser.get('https://www.taobao.com')
browser.get('https://www.python.org')
browser.back()
time.sleep(1)
browser.forward()
browser.close()
cookies
from selenium import webdriver
import time
browser = webdriver.Chrome()
browser.get('https://www.zhihu.com/explore')
print(browser.get_cookies())
browser.add_cookie(
{'name': 'name', 'domain': 'www.zhihu.com', 'value': 'germey'})
print(browser.get_cookies())
browser.delete_all_cookies()
print(browser.get_cookies())
选项卡管理
import time
from selenium import webdriver
browser = webdriver.Chrome()
browser.get('https://www.baidu.com')
browser.execute_script('window.open()')
print(browser.window_handles)
browser.switch_to_window(browser.window_handles[1])
browser.get('https://www.taobao.com')
time.sleep(1)
browser.switch_to_window(browser.window_handles[0])
browser.get('https://python.org')
异常处理
from selenium import webdriver
browser = webdriver.Chrome()
browser.get('https://www.baidu.com')
browser.find_element_by_id('hello')
#会报错selenium.common.exceptions.NoSuchElementException: Message: no such element: Unable to locate element: {"method":"id","selector":"hello"}
from selenium import webdriver
from selenium.common.exceptions import TimeoutException, NoSuchElementException
browser = webdriver.Chrome()
try:
browser.get('https://www.baidu.com')
except TimeoutException:
print('Time Out')
try:
browser.find_element_by_id('hello')
except NoSuchElementException:
print('No Element')
finally:
browser.close()
