selenium之百度搜索，结果列表翻页查询
实例：百度搜索，结果列表翻页查询
解决问题：解决selenium driver获取web页面元素时,元素过期问题
思路1：获取所有“页面翻页链接”元素，然后遍历元素并点击
# -*- coding: utf-8 -*-
fromseleniumimportwebdriver
importtime
if__name__ =="__main__":
driver = webdriver.Firefox()
driver.maximize_window()
driver.get('http://www.baidu.com')
driver.implicitly_wait(5)
driver.find_element_by_id('kw1').send_keys('selenium')
driver.find_element_by_id('su1').click()
page = driver.find_element_by_id('page')
pages = page.find_elements_by_tag_name('a') #查找所有翻页跳转链接
#设置滚动条位置为底部
js ='document.documentElement.scrollTop=10000'
foreachinpages:
driver.execute_script(js) #拖动滚动条到底部
each.click()
driver.execute_script(js)
time.sleep(3)
driver.quit()
结果：点击第3页时，程序出错
selenium.common.exceptions.StaleElementReferenceException: Message: u'Element not found in the cache - perhaps the page has changed since it was looked up' ; Stacktrace:
即在cache中找不到元素，可能是在元素被找到之后页面变换了。这就说明，当前页面发生跳转之后，存在cache中的与这个页面相关的元素也被清空了
思路2：基于思路1的错误结果分析>先获取每个页面数，然后每次点击某个页面，跳转后重新获取下一个页面翻页链接，然后点击，循环。。
# -*- coding: utf-8 -*-
fromseleniumimportwebdriver
importtime
if__name__ =="__main__":
driver = webdriver.Firefox()
driver.maximize_window()
driver.get('http://www.baidu.com')
driver.implicitly_wait(5)
driver.find_element_by_id('kw1').send_keys('selenium')
driver.find_element_by_id('su1').click()
page = driver.find_element_by_id('page')
pages = page.find_elements_by_tag_name('a')
js ='document.documentElement.scrollTop=10000'
total = len(pages)
has_pre_page =False
page_num =0
foriinrange(total):
driver.execute_script(js)
pn=10
page_num = page_num +1#设置页面号
one_page = driver.find_element_by_css_selector('p[id="page"]>a:nth-of-type('+str(page_num)+')')
one_page.click()
#备注以下小段代码描述了页面变化规律，这个得自己去研究
ifnothas_pre_page: #点击第2页时会出现上一页，页号加1
has_pre_page =True
page_num = page_num +1
ifpage_num %7==0:#page_num等于7时，页号减1
page_num = page_num -1
time.sleep(2)
driver.execute_script(js)
time.sleep(2)
time.sleep(3)
driver.quit()
改进版(自动翻页，前翻页后翻页)
# -*- coding: utf-8 -*-
fromseleniumimportwebdriver
importtime
if__name__ =="__main__":
driver = webdriver.Firefox()
driver.maximize_window()
driver.get('http://www.baidu.com')
driver.implicitly_wait(5)
driver.find_element_by_id('kw1').send_keys('selenium selenium')#测试数据selenium zhidashso dld#selenium zhidashso dldld
driver.find_element_by_id('su1').click()
js ='document.documentElement.scrollTop=10000'
total =0 #页面数
is_next_page =True #存在下一页
page_num =0 #要点击的页面号
#往后翻页
whileis_next_page:#'sv_page\=1' in one_page.get_attribute('href')
driver.execute_script(js)
page_num = page_num +1 #设置页号为下一页
total = page_num #记录页面数
value=str(page_num)
try:
#查找指定页面
one_page = driver.find_element_by_css_selector('p[id="page"]>a[href*=pn\='+value+']')
one_page.click()
time.sleep(1)
driver.execute_script(js)
time.sleep(1)
except:
print('no next page')
is_next_page =False
total = total -1
break
#往前翻页
whiletotal >=0:
driver.execute_script(js)
try:
total = total -1
value = str(total)
one_page = driver.find_element_by_css_selector('p[id="page"]>a[href*=pn\='+value+']')
one_page.click()
time.sleep(1)
driver.execute_script(js)
time.sleep(1)
except:
print('no pre page')
break;
time.sleep(3)
driver.quit()
