PYTHON 爬虫笔记七:Selenium库基础用法
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PYTHON 爬虫笔记七:Selenium库基础用法
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知識點一：Selenium庫詳解及其基本使用
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什么是Selenium
selenium 是一套完整的web應用程序測試系統，包含了測試的錄制（selenium IDE）,編寫及運行（Selenium Remote Control）和測試的并行處理（Selenium Grid）。
selenium的核心Selenium Core基于JsUnit，完全由JavaScript編寫，因此可以用于任何支持JavaScript的瀏覽器上。
selenium可以模擬真實瀏覽器，自動化測試工具，支持多種瀏覽器，爬蟲中主要用來解決JavaScript渲染問題。
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基本使用
用python寫爬蟲的時候，主要用的是selenium的Webdriver，我們可以通過下面的方式先看看Selenium.Webdriver支持哪些瀏覽器
基本用法：
#打開google瀏覽器，再打開百度，輸入Python然后按回車 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 WebDriverWaitchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) try:browser.get('https://www.baidu.com')input = browser.find_element_by_id('kw') # 找到id為kw的元素input.send_keys('Python') # 敲入Pythoninput.send_keys(Keys.ENTER) # 敲入回車wait = WebDriverWait(browser, 10)wait.until(EC.presence_of_element_located((By.ID, 'content_left'))) # 等待某個元素加載出來print(browser.current_url)print(browser.get_cookies())print(browser.page_source) # 網頁源代碼 finally:browser.close() https://www.baidu.com/s?ie=utf-8&f=8&rsv_bp=0&rsv_idx=1&tn=baidu&wd=Python&rsv_pq=aa95af1b0000f45e&rsv_t=53e2qpjWA%2FivTq6GgdT4FAhWM%2FWfkPZhHYkLoaS7MVPQUZCHF%2FkLQV2%2Brnc&rqlang=cn&rsv_enter=1&rsv_sug3=6&rsv_sug2=0&inputT=111&rsv_sug4=112 [{'domain': '.baidu.com', 'httpOnly': False, 'name': 'H_PS_PSSID', 'path': '/', 'secure': False, 'value': '1464_21121_26922_22159'}, {'domain': '.baidu.com', 'expiry': 3681286522.89887, 'httpOnly': False, 'name': 'BAIDUID', 'path': '/', 'secure': False, 'value': '410FC9CBBC1B798C0BEF149D5C0BD4E4:FG=1'}, {'domain': '.baidu.com', 'expiry': 3681286522.899111, 'httpOnly': False, 'name': 'BIDUPSID', 'path': '/', 'secure': False, 'value': '410FC9CBBC1B798C0BEF149D5C0BD4E4'}, {'domain': '.baidu.com', 'expiry': 3681286522.899241, 'httpOnly': False, 'name': 'PSTM', 'path': '/', 'secure': False, 'value': '1533802877'}, {'domain': '.baidu.com', 'httpOnly': False, 'name': 'PSINO', 'path': '/', 'secure': False, 'value': '7'}, {'domain': 'www.baidu.com', 'expiry': 2479882880.172246, 'httpOnly': False, 'name': 'delPer', 'path': '/', 'secure': False, 'value': '0'}, {'domain': 'www.baidu.com', 'httpOnly': False, 'name': 'BD_HOME', 'path': '/', 'secure': False, 'value': '0'}, {'domain': 'www.baidu.com', 'expiry': 1534666877, 'httpOnly': False, 'name': 'BD_UPN', 'path': '/', 'secure': False, 'value': '12314753'}, {'domain': 'www.baidu.com', 'httpOnly': False, 'name': 'BD_CK_SAM', 'path': '/', 'secure': False, 'value': '1'}, {'domain': 'www.baidu.com', 'expiry': 1533805472, 'httpOnly': False, 'name': 'H_PS_645EC', 'path': '/', 'secure': False, 'value': 'c9083HSTzGdEsBVBx%2FDjhaEep8Lu5MHd8KusVOaaun2nj5W%2Bjur8%2BSHut%2BM'}] <!DOCTYPE html><!--STATUS OK--><html xmlns="http://www.w3.org/1999/xhtml"><head><script charset="utf-8" async="" src="https://ss0.bdstatic.com/-0U0bnSm1A5BphGlnYG/tam-ogel/5d4e9b24-dcc5-483a-b6da-be1e9e621891.js"></script> 獲得的結果聲明瀏覽器對象（上面我們知道了selenium支持很多的瀏覽器，但是如果想要聲明并調用瀏覽器則需要：）
from selenium import webdriverbrowser = webdriver.Chrome() browser = webdriver.Firefox() browser = webdriver.Edge() browser = webdriver.PhantomJS() browser = webdriver.Safari()訪問頁面
from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.taobao.com') print(browser.page_source) browser.close() <!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml" lang="zh-CN" class="ks-webkit537 ks-webkit ks-chrome68 ks-chrome"><head><script>/*! 2018-08-07 14:58:00 v8.5.7 */ !function(e){function i(n){if(o[n])return o[n].exports;var r=o[n]={exports:{},id:n,loaded:!1};return e[n].call(r.exports,r,r.exports,i),r.loaded=!0,r.exports}var o={};return i.m=e,i.c=o,i.p="",i(0)}([function(e,i){"use strict";var o=window,n=document;!function(){var e=2,r="ali_analytics";if(o[r]&&o[r].ua&&e<=o[r].ua.version)return void(i.info=o[r].ua);var t,a,d,s,c,u,h,l,m,b,f,v,p,w,g,x,z,O=o.navigator,k=O.appVersion,T=O&&O.userAgent||"",y=function(e){var i=0;return parseFloat(e.replace(/\./g,function(){return 0===i++?".":""}))},_=function(e,i){var o,n;i[o="trident"]=.1,(n=e.match(/Trident\/([\d.]*)/))&&n[1]&&(i[o]=y(n[1])),i.core=o},N=function(e){var i,o;return(i=e.match(/MSIE ([^;]*)|Trident.*; rv(?:\s|:)?([0-9.]+)/))&&(o=i[1]||i[2])?y(o):0},P=function(e){return e||"other"},M=function(e){function i(){for(var i=[["Windows NT 5.1","winXP"],["Windows NT 6.1","win7"],["Windows NT 6.0","winVista"],["Windows NT 6.2","win8"],["Windows NT 10.0","win10"],["iPad","ios"],["iPhone;","ios"],["iPod","ios"],["Macintosh","mac"],["Android","android"],["Ubuntu","ubuntu"],["Linux","linux"],["Windows NT 5.2","win2003"],["Windows NT 5.0","win2000"],["Windows","winOther"],["rhino","rhino"]],o=0,n=i.length;o<n;++o)if(e.indexOf(i[o][0])!==-1)return i[o][1];return"other"}function r(e,i,n,r){var t,a=o.navigator.mimeTypes;try{for(t in a)if(a.hasOwnProperty(t)&&a[t][e]==i){if(void 0!==n&&r.test(a[t][n]))return!0;if(void 0===n)return!0}return!1}catch(e){return!1}}var t,a,d,s,c,u,h,l="",m=l,b=l,f=[6,9],v="{{version}}",p="<!--[if IE "+v+"]><s></s><![endif]-->",w=n&&n.createElement("div"),g=[],x={webkit:void 0,edge:void 0,trident:void 0,gecko:void 0,presto:void 0,chrome:void 0,safari:void 0,firefox:void 0,ie:void 0,ieMode:void 0,opera:void 0,mobile:void 0,core:void 0,shell:void 0,phantomjs:void 0,os:void 0,ipad:void 0,iphone:void 0,ipod:void 0,ios:void 0,android:void 0,nodejs:void 0,extraName:void 0,extraVersion:void 0};if(w&&w.getElementsByTagName&&(w.innerHTML=p.replace(v,""),g=w.getElementsByTagName("s")),g.length>0){for(_(e,x),s=f[0],c=f[1];s<=c;s++)if(w.innerHTML=p.replace(v,s),g.length>0){x[b="ie"]=s;break}!x.ie&&(d=N(e))&&(x[b="ie"]=d)}else((a=e.match(/AppleWebKit\/*\s*([\d.]*)/i))||(a=e.match(/Safari\/([\d.]*)/)))&&a[1]?(x[m="webkit"]=y(a[1]),(a=e.match(/OPR\/(\d+\.\d+)/))&&a[1]?x[b="opera"]=y(a[1]):(a=e.match(/Chrome\/([\d.]*)/))&&a[1]?x[b="chrome"]=y(a[1]):(a=e.match(/\/([\d.]*) Safari/))&&a[1]?x[b="safari"]=y(a[1]):x.safari=x.webkit,(a=e.match(/Edge\/([\d.]*)/))&&a[1]&&(m=b="edge",x[m]=y(a[1])),/ Mobile\//.test(e)&&e.match(/iPad|iPod|iPhone/)?(x.mobile="apple",a=e.match(/OS ([^\s]*)/),a&&a[1]&&(x.ios=y(a[1].replace("_","."))),t="ios"。。。。。。。。。。。 獲得的結果查找元素
單個元素
#element from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.taobao.com') input_first = browser.find_element_by_id('q') # 尋找 id='q'的元素 input_second = browser.find_element_by_css_selector('#q') # 通過css選擇器選擇 input_third = browser.find_element_by_xpath('//*[@id="q"]') # 同上 print(input_first, input_second, input_third) browser.close()#這里我們通過三種不同的方式去獲取響應的元素，第一種是通過id的方式，第二個中是CSS選擇器，第三種是xpath選擇器，結果都是相同的。
<selenium.webdriver.remote.webelement.WebElement (session="49795084aea9c702e52e3464a2e602bf", element="0.06918141330676386-1")> <selenium.webdriver.remote.webelement.WebElement (session="49795084aea9c702e52e3464a2e602bf", element="0.06918141330676386-1")> <selenium.webdriver.remote.webelement.WebElement (session="49795084aea9c702e52e3464a2e602bf", element="0.06918141330676386-1")> 獲得的結果
另一種方式：
from selenium import webdriver from selenium.webdriver.common.by import Bychromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.taobao.com') input_first = browser.find_element(By.ID, 'q') print(input_first) browser.close() 另一種方式 <selenium.webdriver.remote.webelement.WebElement (session="2706eb775a80e5eb5af01293caaf84e1", element="0.30861434960698597-1")> --->獲得的結果查找單個元素的方法
* 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
查找多個元素
#elements from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.taobao.com') lis = browser.find_elements_by_css_selector('.service-bd li') print(lis) browser.close() [<selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-1")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-2")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-3")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-4")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-5")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-6")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-7")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-8")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-9")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-10")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-11")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-12")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-13")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-14")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-15")>, <selenium.webdriver.remote.webelement.WebElement (session="1fd716bf2cf93a91caa11907d2ad67c7", element="0.7320173413952247-16")>] 獲得的結果另一種方式：
from selenium import webdriver from selenium.webdriver.common.by import Bychromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.taobao.com') lis = browser.find_elements(By.CSS_SELECTOR, '.service-bd li') print(lis) browser.close() 另一種方式 [<selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-1")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-2")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-3")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-4")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-5")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-6")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-7")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-8")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-9")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-10")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-11")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-12")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-13")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-14")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-15")>, <selenium.webdriver.remote.webelement.WebElement (session="f8d8a0f755dde2eecb7de8970c44d9f5", element="0.5842041920354057-16")>] --->獲得的結果一些其他的方式：
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
先獲取元素。
對獲取的元素調用交互方法
更多操作: http://selenium-python.readthedocs.io/api.html#module-selenium.webdriver.remote.webelement
交互動作（將動作附加到動作鏈中串行執行）
from selenium import webdriver from selenium.webdriver import ActionChainschromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) # 聲明瀏覽器對象 url = 'http://www.runoob.com/try/try.php?filename=jqueryui-api-droppable' browser.get(url) browser.switch_to.frame('iframeResult') #切換到‘iframeResult’框架 source = browser.find_element_by_css_selector('#draggable') # 選擇元素 target = browser.find_element_by_css_selector('#droppable') # 選擇元素 actions = ActionChains(browser) # 聲明一個動作鏈對象 actions.drag_and_drop(source, target) # 拖拽方法 actions.perform() # 執行動作更多操作: http://selenium-python.readthedocs.io/api.html#module-selenium.webdriver.common.action_chains
?執行JavaScript（執行一些交互動作時，可能一些動作沒有提供API。）
#把網頁拉到最下面，并提示 from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) # 聲明瀏覽器對象 browser.get('https://www.zhihu.com/explore') browser.execute_script('window.scrollTo(0, document.body.scrollHeight)') browser.execute_script('alert("To Bottom")')?獲取元素信息
獲取屬性：*.get_attribute(“class”) *
from selenium import webdriver from selenium.webdriver import ActionChainschromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) # 聲明瀏覽器對象 url = 'https://www.zhihu.com/explore' browser.get(url) logo = browser.find_element_by_id('zh-top-link-logo') print(logo) print(logo.get_attribute('class')) browser.close() <selenium.webdriver.remote.webelement.WebElement (session="d5564ba9ec58a9a53015648f61a56bd7", element="0.46068206240103504-1")> zu-top-link-logo 獲得的結果獲取文本值：*text*
from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) # 聲明瀏覽器對象 url = 'https://www.zhihu.com/explore' browser.get(url) input = browser.find_element_by_class_name('zu-top-add-question') print(input.text)#提問獲取ID、位置、標簽名、大小
from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) # 聲明瀏覽器對象 url = 'https://www.zhihu.com/explore' browser.get(url) input = browser.find_element_by_class_name('zu-top-add-question') print(input.id) print(input.location) print(input.tag_name) print(input.size) 0.0866191825002236-1 {'x': 759, 'y': 7} button {'height': 32, 'width': 66} 獲得的結果Frame
在很多網頁中都是有Frame標簽，所以我們爬取數據的時候就涉及到切入到frame中以及切出來的問題，通過下面的例子演示 這里常用的是switch_to.from()和switch_to.parent_frame() 父級的frame要查找子級的frame必須要切換到子frame，否則不能查找。 同理子frame也不能查找父frame的元素。 import time from selenium import webdriver from selenium.common.exceptions import NoSuchElementExceptionchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) url = 'http://www.runoob.com/try/try.php?filename=jqueryui-api-droppable' # 聲明網址 browser.get(url) # get傳入網址 browser.switch_to.frame('iframeResult') # 切換到子frame source = browser.find_element_by_css_selector('#draggable') # 查找子frame中的元素 print(source) try:logo = browser.find_element_by_class_name('logo') except NoSuchElementException:print('NO LOGO') browser.switch_to.parent_frame() # 切換到父frame logo = browser.find_element_by_class_name('logo') print(logo) print(logo.text) <selenium.webdriver.remote.webelement.WebElement (session="7d3651ff77a4266e974a48387a562fe1", element="0.7541880746473664-1")> NO LOGO <selenium.webdriver.remote.webelement.WebElement (session="7d3651ff77a4266e974a48387a562fe1", element="0.04296955550550363-2")> RUNOOB.COM 獲得的結果等待
當使用了隱式等待執行測試的時候，如果WebDriver沒有在 DOM中找到元素，將繼續等待，超出設定時間后則拋出找不到元素的異常, 換句話說，當查找元素或元素并沒有立即出現的時候，隱式等待將等待一段時間再查找DOM，默認的時間是0
隱式等待
到了一定的時間發現元素還沒有加載，則繼續等待我們指定的時間，如果超過了我們指定的時間還沒有加載就會拋出異常，如果沒有需要等待的時候就已經加載完畢就會立即執行 from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.implicitly_wait(10) # 傳入隱式等待的時間 browser.get('https://www.zhihu.com/explore') input = browser.find_element_by_class_name('zu-top-add-question') print(input) <selenium.webdriver.remote.webelement.WebElement (session="7c232ca91150077a6d9ded5a653ebf6d", element="0.019205089543862464-1")> 獲得的結果顯式等待：* .WebDriverWait(對象，最長等待時間)*
指定一個等待條件，并且指定一個最長等待時間，會在這個時間內進行判斷是否滿足等待條件，如果成立就會立即返回，如果不成立，就會一直等待，直到等待你指定的最長等待時間，如果還是不滿足，就會拋出異常，如果滿足了就會正常返回 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 ECchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.taobao.com/') wait = WebDriverWait(browser, 10) # 聲明一個等待對象 # 判斷元素是否加載 input = wait.until(EC.presence_of_element_located((By.ID, 'q'))) # 傳入等待條件 # # 判斷是否可點擊的，一般用來判斷是否為按鈕 button = wait.until(EC.element_to_be_clickable((By.CSS_SELECTOR, '.btn-search'))) print(input, button) <selenium.webdriver.remote.webelement.WebElement (session="ac4d3c5db3d4f3aae7b828ad648e87df", element="0.49320541507860316-1")> <selenium.webdriver.remote.webelement.WebElement (session="ac4d3c5db3d4f3aae7b828ad648e87df", element="0.49320541507860316-2")> 獲得的結果
上述的例子中的條件：
EC.presence_of_element_located()是確認元素是否已經出現了
EC.element_to_be_clickable()是確認元素是否是可點擊的
常用的判斷條件：
title_is 標題是某內容
title_contains 標題包含某內容
presence_of_element_located 元素加載出，傳入定位元組，如(By.ID, 'p')
visibility_of_element_located 元素可見，傳入定位元組
visibility_of 可見，傳入元素對象
presence_of_all_elements_located 所有元素加載出
text_to_be_present_in_element 某個元素文本包含某文字
text_to_be_present_in_element_value 某個元素值包含某文字
frame_to_be_available_and_switch_to_it frame加載并切換
invisibility_of_element_located 元素不可見
element_to_be_clickable 元素可點擊
staleness_of 判斷一個元素是否仍在DOM，可判斷頁面是否已經刷新
element_to_be_selected 元素可選擇，傳元素對象
element_located_to_be_selected 元素可選擇，傳入定位元組
element_selection_state_to_be 傳入元素對象以及狀態，相等返回True，否則返回False
element_located_selection_state_to_be 傳入定位元組以及狀態，相等返回True，否則返回False
alert_is_present 是否出現Alert
更多操作參考：http://selenium-python.readthedocs.io/api.html#module-selenium.webdriver.support.expected_conditions
前進后退：*back()；forward()*
#打開谷歌瀏覽器，然后打開白隊首頁，在打開淘寶，知乎首頁，返回淘寶頁面等待一秒在回到知乎界面 import time from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.baidu.com/') browser.get('https://www.taobao.com/') browser.get('https://www.zhihu.com/') browser.back() time.sleep(1) browser.forward() browser.close()Cookies：*get_cookies()；delete_all_cookes()；add_cookie()*
from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) 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()) [{'domain': '.zhihu.com', 'httpOnly': False, 'name': 'l_n_c', 'path': '/', 'secure': False, 'value': '1'}, {'domain': 'www.zhihu.com', 'expiry': 1533802053.671843, 'httpOnly': False, 'name': 'tgw_l7_route', 'path': '/', 'secure': False, 'value': '156dfd931a77f9586c0da07030f2df36'}, {'domain': '.zhihu.com', 'expiry': 1533802958, 'httpOnly': False, 'name': '__utmb', 'path': '/', 'secure': False, 'value': '51854390.0.10.1533801158'}, {'domain': '.zhihu.com', 'expiry': 1628409153.672149, 'httpOnly': False, 'name': 'q_c1', 'path': '/', 'secure': False, 'value': '5fdfbadd6fc347398cc287ebb19a383c|1533801155000|1533801155000'}, {'domain': 'www.zhihu.com', 'httpOnly': False, 'name': '_xsrf', 'path': '/', 'secure': False, 'value': 'e58e3a1c1f41931b44a67c2b426c2f1e'}, {'domain': '.zhihu.com', 'expiry': 1536393153.672288, 'httpOnly': False, 'name': 'r_cap_id', 'path': '/', 'secure': False, 'value': '"MjI4MWJhNjU3YTRiNGFkMmE0OTkxNjk5MDMxZjc4NTU=|1533801155|61d044a51d2c7f0c8a99b9efcdec2f929a626003"'}, {'domain': '.zhihu.com', 'expiry': 1536393153.672375, 'httpOnly': False, 'name': 'cap_id', 'path': '/', 'secure': False, 'value': '"OTQ3Mjc1NmI0ZWEyNDFiOTkwYjAxYmY5NmU5Y2YyZGY=|1533801155|e2f66995a8136044730315e95ab3230932d3e85a"'}, {'domain': '.zhihu.com', 'expiry': 1536393153.672453, 'httpOnly': False, 'name': 'l_cap_id', 'path': '/', 'secure': False, 'value': '"NzRiMmNiMGQ2ZjYwNGIwM2I2Nzg0OTExNGUxZTJmZTA=|1533801155|9ad2a89322a8cfaf04770121c359a1de82636336"'}, {'domain': '.zhihu.com', 'httpOnly': False, 'name': 'n_c', 'path': '/', 'secure': False, 'value': '1'}, {'domain': '.zhihu.com', 'expiry': 1628409157.390474, 'httpOnly': False, 'name': 'd_c0', 'path': '/', 'secure': False, 'value': '"ALDleMF-Bw6PTmu-31M1eULrY7jjkGvu9tA=|1533801158"'}, {'domain': '.zhihu.com', 'expiry': 1596873157, 'httpOnly': False, 'name': '_zap', 'path': '/', 'secure': False, 'value': '084e48e3-598e-4d8a-85b4-4def087fc321'}, {'domain': '.zhihu.com', 'expiry': 1596873158, 'httpOnly': False, 'name': '__utma', 'path': '/', 'secure': False, 'value': '51854390.543124770.1533801158.1533801158.1533801158.1'}, {'domain': '.zhihu.com', 'httpOnly': False, 'name': '__utmc', 'path': '/', 'secure': False, 'value': '51854390'}, {'domain': '.zhihu.com', 'expiry': 1549569158, 'httpOnly': False, 'name': '__utmz', 'path': '/', 'secure': False, 'value': '51854390.1533801158.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)'}, {'domain': '.zhihu.com', 'expiry': 1596873158, 'httpOnly': False, 'name': '__utmv', 'path': '/', 'secure': False, 'value': '51854390.000--|3=entry_date=20180809=1'}] [{'domain': '.zhihu.com', 'httpOnly': False, 'name': 'l_n_c', 'path': '/', 'secure': False, 'value': '1'}, {'domain': 'www.zhihu.com', 'expiry': 1533802053.671843, 'httpOnly': False, 'name': 'tgw_l7_route', 'path': '/', 'secure': False, 'value': '156dfd931a77f9586c0da07030f2df36'}, {'domain': '.zhihu.com', 'expiry': 1533802958, 'httpOnly': False, 'name': '__utmb', 'path': '/', 'secure': False, 'value': '51854390.0.10.1533801158'}, {'domain': '.zhihu.com', 'expiry': 1628409153.672149, 'httpOnly': False, 'name': 'q_c1', 'path': '/', 'secure': False, 'value': '5fdfbadd6fc347398cc287ebb19a383c|1533801155000|1533801155000'}, {'domain': 'www.zhihu.com', 'httpOnly': False, 'name': '_xsrf', 'path': '/', 'secure': False, 'value': 'e58e3a1c1f41931b44a67c2b426c2f1e'}, {'domain': '.zhihu.com', 'expiry': 1536393153.672288, 'httpOnly': False, 'name': 'r_cap_id', 'path': '/', 'secure': False, 'value': '"MjI4MWJhNjU3YTRiNGFkMmE0OTkxNjk5MDMxZjc4NTU=|1533801155|61d044a51d2c7f0c8a99b9efcdec2f929a626003"'}, {'domain': '.zhihu.com', 'expiry': 1536393153.672375, 'httpOnly': False, 'name': 'cap_id', 'path': '/', 'secure': False, 'value': '"OTQ3Mjc1NmI0ZWEyNDFiOTkwYjAxYmY5NmU5Y2YyZGY=|1533801155|e2f66995a8136044730315e95ab3230932d3e85a"'}, {'domain': '.zhihu.com', 'expiry': 1536393153.672453, 'httpOnly': False, 'name': 'l_cap_id', 'path': '/', 'secure': False, 'value': '"NzRiMmNiMGQ2ZjYwNGIwM2I2Nzg0OTExNGUxZTJmZTA=|1533801155|9ad2a89322a8cfaf04770121c359a1de82636336"'}, {'domain': '.zhihu.com', 'httpOnly': False, 'name': 'n_c', 'path': '/', 'secure': False, 'value': '1'}, {'domain': '.zhihu.com', 'expiry': 1628409157.390474, 'httpOnly': False, 'name': 'd_c0', 'path': '/', 'secure': False, 'value': '"ALDleMF-Bw6PTmu-31M1eULrY7jjkGvu9tA=|1533801158"'}, {'domain': '.zhihu.com', 'expiry': 1596873157, 'httpOnly': False, 'name': '_zap', 'path': '/', 'secure': False, 'value': '084e48e3-598e-4d8a-85b4-4def087fc321'}, {'domain': '.zhihu.com', 'expiry': 1596873158, 'httpOnly': False, 'name': '__utma', 'path': '/', 'secure': False, 'value': '51854390.543124770.1533801158.1533801158.1533801158.1'}, {'domain': '.zhihu.com', 'httpOnly': False, 'name': '__utmc', 'path': '/', 'secure': False, 'value': '51854390'}, {'domain': '.zhihu.com', 'expiry': 1549569158, 'httpOnly': False, 'name': '__utmz', 'path': '/', 'secure': False, 'value': '51854390.1533801158.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)'}, {'domain': '.zhihu.com', 'expiry': 1596873158, 'httpOnly': False, 'name': '__utmv', 'path': '/', 'secure': False, 'value': '51854390.000--|3=entry_date=20180809=1'}, {'domain': 'www.zhihu.com', 'expiry': 2164521158, 'httpOnly': False, 'name': 'name', 'path': '/', 'secure': True, 'value': 'germey'}] [] 獲得的結果選項卡管理
通過執行js命令實現新開選項卡window.open() 不同的選項卡是存在列表里browser.window_handles 通過browser.window_handles[0]就可以操作第一個選項卡 import time from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.baidu.com') browser.execute_script('window.open()') # 通過執行一個js語句來新建選項卡 print(browser.window_handles) # 返回所有的選項卡的引用 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') ['CDwindow-B1E2119962846BA7AED735D128600D3E', 'CDwindow-B231BF356905D63DE59F86F644F77A8F'] 獲得的結果?異常處理
這里的異常比較復雜，官網的參考地址：
http://selenium-python.readthedocs.io/api.html#module-selenium.common.exceptions
這里只進行簡單的演示，查找一個不存在的元素
實例，會報錯
from selenium import webdriverchromedriver = "C:/Program Files (x86)/Google/Chrome/Application/chromedriver" browser = webdriver.Chrome(chromedriver) browser.get('https://www.baidu.com') browser.find_element_by_id('hello') NoSuchElementException Traceback (most recent call last) <ipython-input-15-b8bcc6bfca0b> in <module>()4 browser = webdriver.Chrome(chromedriver)5 browser.get('https://www.baidu.com') ----> 6 browser.find_element_by_id('hello')D:\Anaconda3\lib\site-packages\selenium\webdriver\remote\webdriver.py in find_element_by_id(self, id_)357 element = driver.find_element_by_id('foo')358 """ --> 359 return self.find_element(by=By.ID, value=id_)360 361 def find_elements_by_id(self, id_):D:\Anaconda3\lib\site-packages\selenium\webdriver\remote\webdriver.py in find_element(self, by, value)964 return self.execute(Command.FIND_ELEMENT, {965 'using': by, --> 966 'value': value})['value']967 968 def find_elements(self, by=By.ID, value=None):D:\Anaconda3\lib\site-packages\selenium\webdriver\remote\webdriver.py in execute(self, driver_command, params)318 response = self.command_executor.execute(driver_command, params)319 if response: --> 320 self.error_handler.check_response(response)321 response['value'] = self._unwrap_value(322 response.get('value', None))D:\Anaconda3\lib\site-packages\selenium\webdriver\remote\errorhandler.py in check_response(self, response)240 alert_text = value['alert'].get('text')241 raise exception_class(message, screen, stacktrace, alert_text) --> 242 raise exception_class(message, screen, stacktrace)243 244 def _value_or_default(self, obj, key, default):NoSuchElementException: Message: no such element: Unable to locate element: {"method":"id","selector":"hello"}(Session info: chrome=68.0.3440.75)(Driver info: chromedriver=2.41.578737 (49da6702b16031c40d63e5618de03a32ff6c197e),platform=Windows NT 10.0.17134 x86_64) 獲得的結果轉載于:https://www.cnblogs.com/darwinli/p/9450488.html
總結
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