即使元素存在,WebdriverWait也会失败

Question

这是我的代码:

def CheckQueue(driver):
    qdone = False
    qID_xpath_start = "/html/body/div[5]/form/table/tbody[1]/tr["
    qID_xpath_end = "]/td[2]/a"
    qIDindex = 1
    while qdone == False:
        print "enter loop"
        print driver.find_element_by_xpath(qID_xpath_start+str(qIDindex)+qID_xpath_end).text #This prints
        try:
            element = WebDriverWait(driver, 6000).until(ec.presence_of_element_located(By.XPATH((qID_xpath_start+str(qIDindex)+qID_xpath_end)))) #This fails
            print "found"
        except:
            qdone= True
            print "could not be found"

        print driver.find_element_by_xpath(qID_xpath_start+str(qIDindex)+qID_xpath_end).text
        if qdone == False:
            print driver.find_element_by_xpath(qID_xpath_start+str(qIDindex)+qID_xpath_end).text
            print "testing"

        qIDindex +=1
        print "loop"
    return driver

我得到这个返回(14453是我正在寻找的xpath的链接文本)

enter loop
14453
could not be found
14453
loop

看来我的代码能够找到链接,但是当被要求检查链接是否存在时,它会失败,并激活except语句.如果已经找到并打印出来,它为什么会失败？

此外,它几乎立即失败,即使我已经分配了这么多时间来看.

知道我哪里错了吗？

我试过了

element = WebDriverWait(driver, 6000).until(ec.presence_of_element_located(By.XPATH((qID_xpath_start+str(qIDindex)+qID_xpath_end))))

element = WebDriverWait(driver, 6000).until(EC.presence_of_element_located(By.XPATH((qID_xpath_start+str(qIDindex)+qID_xpath_end))))

element = WebDriverWait(driver, 6000).until(ec.presence_of_element_located(By.XPATH, qID_xpath_start+str(qIDindex)+qID_xpath_end))

element = WebDriverWait(driver, 6000).until(ec.presence_of_element_located(By.xpath, qID_xpath_start+str(qIDindex)+qID_xpath_end))

我使用的是Python 2.7,Selenium 2.43,Firefox 23.0.3

顺便说一句,为了测试是否可以在某些点找到xpath元素,我会抛出几个可能感觉不合适的打印语句.

编辑:当我删除我的try语句时,我收到此错误.

element = WebDriverWait(driver, 6000).until(EC.presence_of_element_located(By.XPATH((qID_xpath_start+str(qIDindex)+qID_xpath_end))))

NameError:未定义全局名称"By"

我的代码中有以下import语句:

from selenium import webdriver
from selenium.common.exceptions import TimeoutException
from selenium.webdriver.support.ui import WebDriverWait # available since 2.4.0
from selenium.webdriver.support import expected_conditions as EC # available since 2.26.0
from selenium.webdriver.support.ui import Select
from selenium.webdriver.common.action_chains import ActionChains

我假设我确实需要添加一个import语句,但我似乎无法找到我如何导入By.

我试过了:

from selenium.webdriver.common.by import By

当我运行它时,我使它超过了该错误但收到此错误:

element = WebDriverWait(driver,6000).until(EC.presence_of_element_located(By.XPATH((qID_xpath_start + str(qIDindex)+ qID_xpath_end))))TypeError:'str'对象不可调用

然后我更新了我的WebDriverWait行以反映alecxe的建议.

element = WebDriverWait(driver, 6000).until(EC.presence_of_element_located((By.XPATH, qID_xpath_start+str(qIDindex)+qID_xpath_end)))

现在它似乎正在起作用.

Answer 1

该WebDriverWait表达式语法是不正确的,它应该是:

WebDriverWait(driver, 60).until(ec.presence_of_element_located((By.XPATH, qID_xpath_start+str(qIDindex)+qID_xpath_end)))

注意传递给presence_of_element_located()方法的元组.

注意这里60是60 秒.

此外,为了成功调试并了解正在发生的事情,让它失败通常会有所帮助 - 删除try/except并查看引发的错误类型.