使用Python学习selenium测试工具-4:查找元素
转自:https://blog.csdn.net/wd168/article/details/51819930
web通常包含了Hyper Text Markup Language (HTML)、Cascading Style Sheets (CSS)和JavaScript。本节主要内容如下:
-
了解更多Selenium webDriver查找元素的知识
-
使用各种浏览器提供的开发工具找到和定位元素
-
多种发现元素的方法:ID、Name、类属性值、XPath、CSS选择器
-
Selenium webDriver中的各种find_element_by方法。
一般的浏览器都有查看源码的功能 。
使用开发工具发现定位器
Firefox的插件Firebug是个好帮手,可以F12或者右键点击元素选择“Inspect Element with Firebug”打开。Firefox的搜素框还可以对XPath或CSS进行查找。
Chrome中可以F12或者右键点击元素选择“Inspect Element”的方式查看代码。查找功能也和Firefox类似。Internet Explorer也有类似功能,不再赘述。
元素查找
find_element_by*系列方法在找到元素的时候返回WebElement实例,否则产生NoSuchElementException异常。另外find_elements_by*系列方法可以一次返回多个元素。
driver.find_element_by_css_selector(‘#search’)
Method | Description | Argument | Example |
find_element_by_id(id) | This method finds an element by the ID attribute value | id: The ID of the element to be found | driver.find_element_by_id(‘search’) |
find_element_by_name(name) | This method finds an element by the name attribute value | name: The name of the element to be found | driver.find_element_by_name(‘q’) |
find_element_by_class_name(name) | This method finds an element by the class attribute value | name: The class name of the element to be found | driver.find_element_by_class_name(‘input-text’) |
find_element_by_tag_name(name) | This method finds an element by its tag name | name: The tag name of the element to be found | driver.find_element_by_tag_name(‘input’) |
find_element_by_xpath(xpath) | This method finds an element using XPath | xpath: The xpath of the element to be found | driver.find_element_by_xpath(‘form[0]/div[0]/input[0]’) |
find_element_by_css_selector(css_selector) | This method finds an element by the CSS selector | css_selector: The CSS selector of the element to be found | |
find_element_by_link_text(link_text) | This method finds an element by the link text | link_text: The text of the element to be found | driver.find_element_by_link_text(‘Log In’) |
find_element_by_partial_link_text(link_text) | This method finds an element by a partial match of its link text | link_text: The text to match part of the text of the element | driver.find_element_by_partial_link_text(‘Log’) |
通过id、name、类属性是最建议,也是最快速的查找方法,尤其是id和name。其次使用tag和链接文本,万不得已才使用xpath和css。
XPath即为XML路径语言(XML Path Language),它是一种用来确定XML文档中某部分位置的语言。参考:XPath维基百科介绍 以及w3schools的Xpath介绍,zvon的XPath 1.0介绍。参考书籍:Selenium Testing Tools Cookbook。注意XPath的速度会比CSS还慢,不过支持向前向后定义和相对路径。
层叠样式表(英语:Cascading Style Sheets,简写CSS),又称串样式列表、层次结构式样式表文件,一种用来为结构化文档(如HTML文档或XML应用)添加样式(字体、间距和颜色等)的计算机语言。参考CSS维基百科介绍,w3schools之CSS介绍 和
实例
- import unittest
- from selenium import webdriver
- class HomePageTest(unittest.TestCase):
- @classmethod
- def setUpClass(cls):
- # create a new Firefox session
- cls.driver = webdriver.Firefox()
- cls.driver.implicitly_wait(30)
- cls.driver.maximize_window()
- # navigate to the application home page
- cls.driver.get('http://demo-store.seleniumacademy.com/')
- def test_search_text_field_max_length(self):
- # get the search textbox
- search_field = self.driver.find_element_by_id('search')
- # check maxlength attribute is set to 128
- self.assertEqual('128', search_field.get_attribute('maxlength'))
- def test_search_button_enabled(self):
- # get Search button
- search_button = self.driver.find_element_by_class_name('button')
- # check Search button is enabled
- self.assertTrue(search_button.is_enabled())
- def test_my_account_link_is_displayed(self):
- # get the Account link
- account_link = self.driver.find_element_by_link_text('ACCOUNT')
- # check My Account link is displayed/visible in the Home page footer
- self.assertTrue(account_link.is_displayed())
- def test_account_links(self):
- # get the all the links with Account text in it
- account_links = self.driver.\
- find_elements_by_partial_link_text('ACCOUNT')
- # check Account and My Account link is displayed/visible in the Home page footer
- self.assertTrue(len(account_links), 2)
- def test_count_of_promo_banners_images(self):
- # get promo banner list
- banner_list = self.driver.find_element_by_class_name('promos')
- # get images from the banner_list
- banners = banner_list.find_elements_by_tag_name('img')
- # check there are 3 banners displayed on the page
- self.assertEqual(3, len(banners))
- def test_vip_promo(self):
- # get vip promo image
- vip_promo = self.driver.\
- find_element_by_xpath("//img[@alt='Shop Private Sales - Members Only']")
- # check vip promo logo is displayed on home page
- self.assertTrue(vip_promo.is_displayed())
- # click on vip promo images to open the page
- vip_promo.click()
- # check page title
- self.assertEqual("VIP", self.driver.title)
- def test_shopping_cart_status(self):
- # check content of My Shopping Cart block on Home page
- # get the Shopping cart icon and click to open the Shopping Cart section
- shopping_cart_icon = self.driver.\
- find_element_by_css_selector('div.header-minicart span.icon')
- shopping_cart_icon.click()
- # get the shopping cart status
- shopping_cart_status = self.driver.\
- find_element_by_css_selector('p.empty').text
- self.assertEqual('You have no items in your shopping cart.',
- shopping_cart_status)
- # close the shopping cart section
- close_button = self.driver.\
- find_element_by_css_selector('div.minicart-wrapper a.close')
- close_button.click()
- @classmethod
- def tearDownClass(cls):
- # close the browser window
- cls.driver.quit()
- if __name__ == '__main__':
- unittest.main(verbosity=2)
执行结果:
# python homepagetest.py
test_account_links (__main__.HomePageTest) ... ok
test_count_of_promo_banners_images (__main__.HomePageTest) ... ok
test_my_account_link_is_displayed (__main__.HomePageTest) ... ok
test_search_button_enabled (__main__.HomePageTest) ... ok
test_search_text_field_max_length (__main__.HomePageTest) ... ok
test_shopping_cart_status (__main__.HomePageTest) ... ok
test_vip_promo (__main__.HomePageTest) ... ok
----------------------------------------------------------------------
Ran 7 tests in 77.086s
OK