selenium - Failed to execute 'evaluate' on 'Document': The string is not a valid XPath expression

问题

There is the following page.

http://remitly.com/us/en/

When you click on a select, a list with countries appears. I try to select one country, for example, Colombia and click on it. But I get an error.

SyntaxError: Failed to execute 'evaluate' on 'Document': The string '//span[contains(@class, 'md_countryName_fdxiah8' and text(), 'Colombia')]' is not a valid XPath expression.

select = driver.find_element_by_class_name('f1wrnyr7')
select.click()
countries = driver.find_element_by_class_name('f1o6pohl')
country = countries.find_element_by_xpath("//span[contains(@class, 'md_countryName_fdxiah8' and text(), 'Colombia')]")

回答1:

This error message...

SyntaxError: Failed to execute 'evaluate' on 'Document': The string '//span[contains(@class, 'md_countryName_fdxiah8' and text(), 'Colombia')]' is not a valid XPath expression.

...implies that the XPath which you have used was not a valid XPath expression.

Seems you were pretty close. You can use either of the following Locator Strategies:

• Using xpath 1:

  country = countries.find_element_by_xpath("//span[contains(@class, 'md_countryName_fdxiah8') and text()='Colombia']")
  

• Using xpath 2:

  country = countries.find_element_by_xpath("//span[contains(@class, 'md_countryName_fdxiah8') and contains(., 'Colombia')]")
  

Here you can find a relevant discussion on SyntaxError: Failed to execute 'evaluate' on 'Document': The string '//img[contains('1236548597')]' is not a valid XPath expression

---

Update

To overcome the element not visible error you need to induce WebDriverWait for visibility_of_element_located() and you can use either of the following Locator Strategy:

element = WebDriverWait(driver, 20).until(EC.visibility_of_element_located((By.XPATH, "//span[contains(@class, 'md_countryName_fdxiah8') and text()='Colombia']")))

回答2:

perhaps you were trying something like this (change xpaths as follows, based on your needs):

notice here that the text node should be equal to 'Colombia': //span[contains(@class, 'md_countryName_fdxiah8') and text()='Colombia']

or, the text node might contain some long text, but should also contain 'Colombia' in that text:

//span[contains(@class, 'md_countryName_fdxiah8') and contains(text(), 'Colombia')]

回答3:

Looks like you forgot to attach a link to the page. Anyway, the XPath expression is invalid, the corrected version may be:

//span[contains(@class, 'md_countryName_fdxiah8') and text()='Colombia']\

You can test it with the following XML:

<span class="md_countryName_fdxiah8">Colombia</span>

Result:

Element='<span class="md_countryName_fdxiah8">Colombia</span>'

回答4:

From my experience, Select element are better handled with Select function object. Then each of the list contnet can be addressed by its text

You should import:

from selenium.webdriver.support.ui import Select

And then

select = Select(driver.find_element_by_class_name('f1wrnyr7'))
select.select_by_visible_text('Colombia')

来源：https://stackoverflow.com/questions/57570395/selenium-failed-to-execute-evaluate-on-document-the-string-is-not-a-valid