java - 为什么我的所有页面数据都显示 StaleElementReferenceException

Question

显示堆栈溢出错误

public static void main(String[] args) throws Exception {
    System.setProperty("webdriver.chrome.driver","/home/arima/chromedriver/chromedriver");
    WebDriver driver = new ChromeDriver();
    driver.manage().timeouts().implicitlyWait(20,TimeUnit.SECONDS);
    driver.get("http://education-india.in/Education/Courses/?PageNumber=1");
    Thread.sleep(5000);

    List<WebElement> dropdown = driver.findElements(By.xpath("//select[@id='txtPageNumber']/option"));

    for(int k=1;k<dropdown.size()-1;k++) {
        List<WebElement> rows = driver.findElements(By.xpath("//table[@class='index']/tbody/tr"));
        List<WebElement> col = driver.findElements(By.xpath("//table[@class='index']/tbody/tr[1]/th"));

        for(int i=0;i<rows.size()-1;i++){
            System.out.println(rows.get(i).getText());
        }

        dropdown.get(k).click();
        Thread.sleep(4000);

        /*
         * WebDriverWait wait = new WebDriverWait(driver, 10);
         * wait.until(ExpectedConditions.presenceOfElementLocated(dropdown));
         */
    }
}

Answer 1

stale element reference: element is not attached to the page document 

当 webdriver 无法识别该页面上的元素时，就会出现错误。您需要在 for 循环内重新分配下拉元素。请尝试以下代码。

driver.get("http://education-india.in/Education/Courses/?PageNumber=1");
    WebDriverWait wait=new WebDriverWait(driver, 30);
        List<WebElement> dropdown =wait.until(ExpectedConditions.presenceOfAllElementsLocatedBy(By.xpath("//select[@id='txtPageNumber']/option")));


        for(int k=1;k<dropdown.size()-1;k++) {
            List<WebElement> newdropdown =wait.until(ExpectedConditions.presenceOfAllElementsLocatedBy(By.xpath("//select[@id='txtPageNumber']/option")));

            List<WebElement> rows = driver.findElements(By.xpath("//table[@class='index']/tbody/tr"));
            List<WebElement> col = driver.findElements(By.xpath("//table[@class='index']/tbody/tr[1]/th"));

            for(int i=0;i<rows.size()-1;i++){
                System.out.println(rows.get(i).getText());
            }

            newdropdown.get(k).click();

        }