[Python crawler] Introduction to the method and operation of common element localization in selenium

This article mainly Selenium+python automatic test or crawler in the common positioning methods, mouse operation, keyboard operation introduction,Hope that the basic article is helpful to you, if there are errors or shortcomings, please Haihan ~
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[python crawler] selenium automatically access Firefox and Chrome and implement search
[python crawler] Selenium implement automatic login 163 mailbox and locating elements Introduction
[Python crawler] SELENIUM+PHANTOMJS dynamic Get csdn Download resource information and comments

I. Positioning element Methods
Website address:http://selenium-python.readthedocs.org/locating-elements.html
here are a variety of strategies for locating elements in a Web page (locate elements), you can choose the most appropriate scenario, selenium provides a way to define the elements of a page:

• find_element_by_id
• 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

here's how to find multiple elements (these methods will return a list):

• f Ind_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

In addition to the public methods given above, there are two private methods that are useful in the Page object locator. These two private methods are find_element and find_elements.
The common method is to use the XPath relative path to locate, and CSS is a better method. Example:

 Here's how to locate the username element:
Username = Driver.find_element_by_xpath ("//form[input/@name = ' username ']") Username = Driver.find_element_by_xpath (" form[@id = ' loginform ']/input[1] ") Username = Driver.find_element_by_xpath ("//input[@name = ' username '] ")
[1] The first FORM element is implemented by an input child element, the Name property and the value username
[2] The first input child element is found by a form element of the Id=loginform value
[3] The first INPUT element with the name of the property named name and a value of username

Two. Operation Element Method
After describing the anchored object (locate elements) we need to manipulate the anchored object, usually all the operations and page interaction will pass through the Webelement interface, the common operation element method is as follows:

 
 

  
  
 
   
Clear clears the contents of an element
 
   
Send_keys Analog Key input
 
   
Click on the element
 
   
Submit Form
 
  
 
 
For example, automatic access to Firefox browser automatically login 163 mailbox.
From selenium import webdriver from  selenium.webdriver.common.keys import keys  import time# Login 163 Emaildriver = Webdriver. Firefox ()  driver.get ("http://mail.163.com/") Elem_user = Driver.find_element_by_name ("username") elem_ User.clearelem_user.send_keys ("15201615157")  elem_pwd = driver.find_element_by_name ("password") elem_ Pwd.clearelem_pwd.send_keys ("******")  Elem_pwd.send_keys (Keys.return) #driver. find_element_by_id ("Loginbtn") ). Click () #driver. find_element_by_id ("Loginbtn"). Submit () Time.sleep (5)  assert "Baidu" in Driver.title  Driver.close ()  driver.quit ()  
first locate the user name and password by name, then call the method Clear () Clear the Input box default content, such as "Please enter password" and other prompts, through Send_keys ("* *") enter the correct user name and password, and finally through click () Click the login button or Send_keys (Keys.return) is equivalent to enter login, submit () Submission form. 
PS: If you need to input Chinese, prevent encoding error using Send_keys (U "Chinese user name").


three. Webelement interface Get value
Common values can be obtained through the Webelement interface, which is equally important.

 
 

  
  

  
Size gets the dimensions of the element
  
  

  
Text gets the literal of the element
  
  

  
Get_attribute (name) Gets the property value
  
  

  
Location gets the element coordinates, first finds the element to get, and then calls the method
  
  

  
Page_source back to page source code

  
  

  
Driver.title return page title
  
  

  
Current_url gets the URL of the current page
  
  

  
Is_displayed () sets whether the element is visible
  
  

  
Is_enabled () Determine if the element is being used
  
  

  
Is_selected () Determines whether the element is selected
  
  

  
Tag_name returns the tagname of the element
 
 
The example code is as follows:
from Selenium import webdriver from Selenium.webdriver.common.keys import keys import t Imedriver = Webdriver. Phantomjs (executable_path= "G:\phantomjs-1.9.1-windows\phantomjs.exe") driver.get ("http://www.baidu.com/") size = Driver.find_element_by_name ("WD"). Sizeprint size# Size: {' width ': $, ' height ': 22}news = Driver.find_element_by_xpath ( "//div[@id = ' U1 ']/a[1]"). Textprint news# text: News href = Driver.find_element_by_xpath ("//div[@id = ' U1 ']/a[2]"). get_ Attribute (' href ') name = Driver.find_element_by_xpath ("//div[@id = ' U1 ']/a[2]"). Get_attribute (' name ') print Href,name #属性值: http://www.hao123.com/tj_trhao123location = Driver.find_element_by_xpath ("//div[@id = ' U1 ']/a[3]"). Locationprint location# coordinates: {' y ': +, ' x ': 498}print driver.current_url# Current Link: https://www.baidu.com/print driver.title# Title: Baidu a bit, you know result = Location = driver.find_element_by_id ("su"). is_displayed () Print result# is visible: True 
where the picture is interpreted as shown. 


four. Mouse Operation
In real-world automated tests, the mouse operation is more than just click (), and there are many operations included in the Actionchains class. As follows:

 
 

  
  
 
   
Context_click (Elem) Right click on the mouse click on the element Elem, save as behavior
 
   
Double_click (elem) Double click the mouse click on the element Elem, the map Web can achieve amplification function
 
   
Drag_and_drop (source,target) Drag the mouse, the source element press the left key to move to the target element release
 
   
Move_to_element (Elem) mouse moves to an element
 
   
Click_and_hold (Elem) Press the left mouse button on an element
 
   
Perform () performs the stored behavior in Actionchains by calling the function
 
  
 
 
For example, get the right mouse button saved as Baidu image logo. Code:
import timefrom Selenium import webdriverfrom selenium.webdriver.common.keys Import Keysfrom selenium.webdriver.common.action_chains Import actionchainsdriver = Webdriver. Firefox () driver.get ("http://www.baidu.com") #鼠标移动至图片上 right-click to save picture Elem_pic = Driver.find_element_by_xpath ("//div[@id = ') LG ']/IMG ') print elem_pic.get_attribute ("src") action = Actionchains (Driver). Move_to_element (Elem_pic) Action.context_click (elem_pic) #重点: When right mouse click keyboard cursor down then move to right menu first option Action.send_keys (Keys.arrow_down) time.sleep (3) Action.send_keys (' V ') #另存为action. Perform () #获取另存为对话框 (failed) Alert.switch_to_alert () alert.accept () 
As shown in the effect, navigate to the picture position with XPath and right-click the mouse and select "Save as Picture" in the pop-up menu. But how to click on the "Save As Dialog" button is a difficult, at present, just learning stage, the realm has not been able to solve. Reason:
Webdriver cannot directly interact with dialog Windows this was because dialog windows is the domain of the operating Syst Em and not the webpage.

This section recommends reference materials:
Selenium right-click Download image, combined with Sikuli-tobecrazy
Analysis and extension of mouse and keyboard events in Selenium Webdriver
Selenium Windows Save/open Open dialouge-stackover
Book "Selenium2 python Automation Test" bug Master 

Five. Keyboard Operation
Reference: http://selenium-python.readthedocs.org/api.html
The mouse operation is described earlier and the keyboard operation is now described. All keyboard keystrokes are provided in the keys class of Webdriver, and of course include some common key combinations such as CTRL + A (select all), CTRL + C (copy), and Ctrl + V (paste). More keys refer to the encoding for the official documentation.

 
 

  
  

  
Send_keys (keys.enter) Press ENTER
  
  

  
Send_keys (Keys.tab) Press the Tab tab
  
  

  
Send_keys (Keys.space) Press the space bar space
  
  

  
Send_keys (Kyes.escape) Press the REWIND key ESC
  
  

  
Send_keys (keys.back_space) Press the DELETE key backspace
  
  

  
Send_keys (Keys.shift) Press the SHIFT key
  
  

  
Send_keys (Keys.control) hold down the CTRL key
  
  

  
Send_keys (Keys.arrow_down) Press the mouse cursor down button
  
  

  
Send_keys (Keys.control, ' a ') key combination all Select Ctrl + A
  
  

  
Send_keys (Keys.control, ' C ') key combination copy Ctrl + C
  
  

  
Send_keys (Keys.control, ' x ') combined key shear Ctrl+x
  
  

  
Send_keys (Keys.control, ' V ') bonding Ctrl + V
 
 
The examples used here refer to the insect Master's book "Selenium2 Python Automation Test", which is recommended for everyone. Code is very interesting, we have to feel the next ~
 #coding =utf-8import timefrom Selenium Import Webdriverfrom Selenium.webdriver.common.keys Import keysdriver = Webdriver. Firefox () driver.get ("http://www.baidu.com") #输入框输入内容elem = driver.find_element_by_id ("kw") Elem.send_keys (" Eastmount CSDN ") time.sleep (3) #删除一个字符CSDN Rewind key Elem.send_keys (keys.back_space) Elem.send_keys (keys.back_space) Elem.send_keys (Keys.back_space) Elem.send_keys (keys.back_space) time.sleep (3) #输入空格 + "blog" Elem.send_keys (Keys.SPACE ) Elem.send_keys (U "blog") time.sleep (3) #ctrl +a Select all input box Contents Elem.send_keys (Keys.control, ' a ') Time.sleep (3) #ctrl +x Cut input Box Contents Elem.send_keys (Keys.control, ' x ') Time.sleep (3) #输入框重新输入搜索elem. Send_keys (Keys.control, ' V ') time.sleep (3) # Use the ENTER key to replace the click Operation driver.find_element_by_id ("Su"). Send_keys (Keys.enter) time.sleep (3) driver.quit () 
 Finally hope that the article will help you, if there are errors or shortcomings, please Haihan ~ at the same time to learn the next Linux and the author of the article.
Http://www.dotblogs.com.tw/larrynung/archive/2012/09/26/75065.aspx
(By:eastmount 2016-7-10 1 o'clock in the afternoon http://blog.csdn.net/eastmount/)

[Python crawler] Introduction to the method and operation of common element localization in selenium