selenium.common.exceptions.WebDriverException: Message: unknown error: 'script' must be a string while using execute_script() through Selenium Python

问题

I've got an issue with browser.execute_script while using selenium with python. There is an element that i'd like to click (it's xpath below)

"//*[@id='listFav_FI410_23244709400000_FAGNNURROR_IPOF_APP_P43070_W43070A_CP000A001_40']/table/tbody/tr/td[1]"

I try to do it with:

navMenu = browser.find_element_by_xpath("//*[@id='listFav_FI410_23244709400000_FAGNNURROR_IPOF_APP_P43070_W43070A_CP000A001_40']/table/tbody/tr/td[1]")
time.sleep(3)
browser.execute_script(navMenu.click())

And it works (So it clicks desired element) but right after doing it it throws an error that terminates the script:

selenium.common.exceptions.WebDriverException: Message: unknown error: 'script' must be a string

What am I doing wrong? Is there a way to skip this error? Thx for wasting your time on helping me :)

回答1:

This error message...

selenium.common.exceptions.WebDriverException: Message: unknown error: 'script' must be a string

...implies that the method execute_script() was invoked with wrong type of parameters.

The execute_script() method is defined as:

execute_script(script, *args)
    Synchronously Executes JavaScript in the current window/frame.

Where:
    script: The JavaScript to execute
    *args: Any applicable arguments for your JavaScript.

In your code trial executeScript() method will take the reference of the element as arguments[0] along with the method to be performed (in this case click()) and the reference should be provided thereafter. So @Andersson's solution should have worked.

navMenu = browser.find_element_by_xpath("//*[@id='listFav_FI410_23244709400000_FAGNNURROR_IPOF_APP_P43070_W43070A_CP000A001_40']/table/tbody/tr/td[1]")
browser.execute_script("arguments[0].click()", navMenu)

You can find a detailed discussion in What does argument [0] and argument [1] mean in javascriptexecutor in Selenium WebDriver?

---

The hint to your main issue is the error element not visible which implies either of the following cases:

• You are trying to invoke click() even before the element is visible/clickable
• Element is not within the Viewport when click() was invoked.

Solution

Two pottential solutions will be as follows:

• Induce WebDriverWait for the element to be clickable as follows:

  from selenium.webdriver.support.ui import WebDriverWait
  from selenium.webdriver.common.by import By
  from selenium.webdriver.support import expected_conditions as EC
  # other lines of code
  WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.XPATH, "//*[@id='listFav_FI410_23244709400000_FAGNNURROR_IPOF_APP_P43070_W43070A_CP000A001_40']/table/tbody/tr/td[1]"))).click()
  

• Use executeScript() method to bring the element within the Viewport and then invoke click() as follows:

  navMenu = browser.find_element_by_xpath("//*[@id='listFav_FI410_23244709400000_FAGNNURROR_IPOF_APP_P43070_W43070A_CP000A001_40']/table/tbody/tr/td[1]")
  browser.execute_script("arguments[0].scrollIntoView(true);",navMenu);
  navMenu.click()
  

回答2:

Instead of

browser.execute_script(navMenu.click())

try

browser.execute_script('arguments[0].click();', navMenu)

or

navMenu.click()

回答3:

The correct way to execute a script is to actually write a JavaScript script!.

The click() function of selenium is on the element of the DOM you have located not a script.

As @Andersson suggested try browser.execute_script('arguments[0].click();', navMenu)

I can see you added a sleep for 3 seconds... Using Selenium we generally use WebDriverWait you can learn more about wait's here.

If it's too complicated you can just start with driver.implicitly_wait(3) instead of sleep.

Edit:

If the Element is not displayed yet you can just use navMenu.is_displayed()

Hope this helps you.

来源：https://stackoverflow.com/questions/52187248/selenium-common-exceptions-webdriverexception-message-unknown-error-script