一、webdriver继承关系

在selenium中，无论是常用的Firefox Driver 还是Chrome Driver和Ie Drive，他们都继承至selenium\webdriver\remote下webdriver.py中的WebDriver 类，如下

chrome WebDriver

selenium\webdriver\chrome下webdriver.py中WebDriver定义如下

from selenium.webdriver.remote.webdriver importWebDriver as RemoteWebDriverclassWebDriver(RemoteWebDriver):"""Controls the ChromeDriver and allows you to drive the browser."""

firefox WebDriver

selenium\webdriver\firefox 下webdriver.py中WebDriver定义如下

from selenium.webdriver.remote.webdriver importWebDriver as RemoteWebDriverclassWebDriver(RemoteWebDriver):pass

ie WebDriver

selenium\webdriver\ie  下webdriver.py中WebDriver定义如下

from selenium.webdriver.remote.webdriver importWebDriver as RemoteWebDriverclassWebDriver(RemoteWebDriver):def __init__(self, executable_path='IEDriverServer.exe', capabilities=None,

port=DEFAULT_PORT, timeout=DEFAULT_TIMEOUT, host=DEFAULT_HOST,

log_level=DEFAULT_LOG_LEVEL, log_file=DEFAULT_LOG_FILE):

......

如上源码：from selenium.webdriver.remote.webdriver import WebDriver as RemoteWebDriver 都是继承至RemoteWebDriver ，并主要重写__init__方法

其他方法主要继承至父类RemoteWebDriver ，因此着重看下RemoteWebDriver 类中的方法

1、find类

编写脚本常用的查找页面元素方法

deffind_element_by_id(self, id_):#Finds an element by id.'''

pass

deffind_elements_by_id(self, id_):#Finds multiple elements by id.

pass

deffind_element_by_xpath(self, xpath):#Finds an element by xpath.

pass

deffind_elements_by_xpath(self, xpath):#Finds multiple elements by xpath.

pass

deffind_element_by_link_text(self, link_text):#Finds an element by link text

pass

deffind_elements_by_link_text(self, text):#Finds elements by link text.

pass

deffind_element_by_partial_link_text(self, link_text):#Finds elements by a partial match of their link text.

pass

deffind_elements_by_partial_link_text(self, link_text):#Finds an element by a partial match of its link text.

pass

deffind_element_by_name(self, name):#Finds an element by name.

pass

deffind_elements_by_name(self, name):#Finds elements by name.

pass

deffind_element_by_tag_name(self, name):#Finds an element by tag name.

pass

deffind_elements_by_tag_name(self, name):#Finds elements by tag name.

pass

deffind_element_by_class_name(self, name):

Finds an element byclassname.pass

deffind_elements_by_class_name(self, name):#Finds elements by class name.

pass

deffind_element_by_css_selector(self, css_selector):#Finds an element by css selector.

pass

deffind_elements_by_css_selector(self, css_selector):#Finds elements by css selector.

pass

def find_element(self, by=By.ID, value=None):#'Private' method used by the find_element_by_* methods.

pass

def find_elements(self, by=By.ID, value=None):#'Private' method used by the find_elements_by_* methods.

pass

通过查看源码，其实以上方法都是通过调用

self.find_element(by=By.XXX, value=name)或者self.find_elements(by=By.XXX, value=name)方法来重新定义的

def find_element(self, by=By.ID, value=None):"""'Private' method used by the find_element_by_* methods.

:Usage:

Use the corresponding find_element_by_* instead of this.

:rtype: WebElement"""

ifself.w3c:if by ==By.ID:

by=By.CSS_SELECTOR

value= '[id="%s"]' %valueelif by ==By.TAG_NAME:

by=By.CSS_SELECTORelif by ==By.CLASS_NAME:

by=By.CSS_SELECTOR

value= ".%s" %valueelif by ==By.NAME:

by=By.CSS_SELECTOR

value= '[name="%s"]' %valuereturnself.execute(Command.FIND_ELEMENT, {'using': by,'value': value})['value']

其中by.XXX是selenium\webdriver\common下by.py文件中By类定义的静态常量

classBy(object):"""Set of supported locator strategies."""ID= "id"XPATH= "xpath"LINK_TEXT= "link text"PARTIAL_LINK_TEXT= "partial link text"NAME= "name"TAG_NAME= "tag name"CLASS_NAME= "class name"CSS_SELECTOR= "css selector"

通过以上分析，不难发现，只要掌握了self.find_element(by=By.XXX, value=name)或者self.find_elements(by=By.XXX, value=name)方法，已就意味着掌握了全部的查找定位页面元素的方法

2、除了常用的find类方法外，以下方法在编写脚本是也是常用的

ef get(self, url):"""Loads a web page in the current browser session."""@propertydeftitle(self):"""Returns the title of the current page."""@propertydefcurrent_url(self):"""Gets the URL of the current page."""@propertydefcurrent_window_handle(self):"""Returns the handle of the current window."""

defmaximize_window(self):"""Maximizes the current window that webdriver is using"""@propertydefswitch_to(self):returnself._switch_to#Target Locators

defswitch_to_active_element(self):"""Deprecated use driver.switch_to.active_element"""

defswitch_to_window(self, window_name):"""Deprecated use driver.switch_to.window"""

defswitch_to_frame(self, frame_reference):"""Deprecated use driver.switch_to.frame"""

defswitch_to_default_content(self):"""Deprecated use driver.switch_to.default_content"""

defswitch_to_alert(self):"""Deprecated use driver.switch_to.alert"""

其中使用@property修饰的，可以当作为属性来使用，如driver.current_url

3、为什么在实际应用过程中通过from selenium import webdriver引入webdriver，然后通过webdriver.Chrome()就可以实例化Chrome的Driver对象呢？

从以上selenium目录结构，理论上需要通过以下来导入

#导入chrome的WebDriver

from selenium.webdriver.chrome.webdriver importWebDriver#导入firefox的WebDriver

from selenium.webdriver.firefox.webdriver importWebDriver#导入ie的WebDriver

from selenium.webdriver.ie.webdriver import WebDriver

selenium项目目录结构

selenium

│ __init__.py

│

├─common

│ │ exceptions.py

│ │ __init__.py

│

├─webdriver

│ │ __init__.py

│ │

│ ├─android

│ │ │ webdriver.py

│ │ │ __init__.py

│ │

│ ├─blackberry

│ │ │ webdriver.py

│ │ │ __init__.py

│ │

│ ├─chrome

│ │ │ options.py

│ │ │ remote_connection.py

│ │ │ service.py

│ │ │ webdriver.py

│ │ │ __init__.py

│ │

│ ├─common

│ │ │ action_chains.py

│ │ │ alert.py

│ │ │ by.py

│ │ │ desired_capabilities.py

│ │ │ keys.py

│ │ │ proxy.py

│ │ │ service.py

│ │ │ touch_actions.py

│ │ │ utils.py

│ │ │ __init__.py

│ │ │

│ │ ├─actions

│ │ │ │ action_builder.py

│ │ │ │ input_device.py

│ │ │ │ interaction.py

│ │ │ │ key_actions.py

│ │ │ │ key_input.py

│ │ │ │ mouse_button.py

│ │ │ │ pointer_actions.py

│ │ │ │ pointer_input.py

│ │ │ │ __init__.py

│ │ │

│ │ │

│ │ ├─html5

│ │ │ │ application_cache.py

│ │ │ │ __init__.py

│ │

│ ├─edge

│ │ │ options.py

│ │ │ service.py

│ │ │ webdriver.py

│ │ │ __init__.py

│ ├─firefox

│ │ │ extension_connection.py

│ │ │ firefox_binary.py

│ │ │ firefox_profile.py

│ │ │ options.py

│ │ │ remote_connection.py

│ │ │ service.py

│ │ │ webdriver.py

│ │ │ webdriver.xpi

│ │ │ webdriver_prefs.json

│ │ │ webelement.py

│ │ │ __init__.py

│ │

│ ├─ie

│ │ │ service.py

│ │ │ webdriver.py

│ │ │ __init__.py

│ ├─opera

│ │ │ options.py

│ │ │ webdriver.py

│ │ │ __init__.py

│ ├─phantomjs

│ │ │ service.py

│ │ │ webdriver.py

│ │ │ __init__.py

│ ├─remote

│ │ │ command.py

│ │ │ errorhandler.py

│ │ │ file_detector.py

│ │ │ getAttribute.js

│ │ │ isDisplayed.js

│ │ │ mobile.py

│ │ │ remote_connection.py

│ │ │ switch_to.py

│ │ │ utils.py

│ │ │ webdriver.py

│ │ │ webelement.py

│ │ │ __init__.py

│ ├─safari

│ │ │ service.py

│ │ │ webdriver.py

│ │ │ __init__.py

│ ├─support

│ │ │ abstract_event_listener.py

│ │ │ color.py

│ │ │ events.py

│ │ │ event_firing_webdriver.py

│ │ │ expected_conditions.py

│ │ │ select.py

│ │ │ ui.py

│ │ │ wait.py

│ │ │ __init__.py

通过查看selenium\webdriver下__init__.py文件发现

from .firefox.webdriver import WebDriver as Firefox #noqa

from .firefox.firefox_profile import FirefoxProfile #noqa

from .chrome.webdriver import WebDriver as Chrome #noqa

from .chrome.options import Options as ChromeOptions #noqa

from .ie.webdriver import WebDriver as Ie #noqa

其实是因为该出已经导入了，所以才可以直接使用Firefox、Chrome