selenium - System.NotImplementedException : Element is no longer valid -Selenium Webdriver

Question

这让我发疯，我尝试使用 By.Id or By.Xpath但没有一个有效，这是我的Select Method试图从下拉列表中选择文本

//测试代码

 SelectMyText(By.XPath("//*[@id='ctl00_ContentPlaceHolder1_ddlCategory']"), "Employee");

//方法:

     public void SelectMyText(By locator, string valueToBeSelected)
    {
        var options = GetElementId(locator).FindElements(By.TagName("option"));
        foreach (var option in options)
        {
            if (valueToBeSelected == option.Text)
            {
                option.Click();
                return;
            }
        }
    }

    public IWebElement GetElementId(By locator)
    {
        return Driver.FindElement(locator);
    }

这是得到的错误:

threw exception: 
System.NotImplementedException: Element is no longer valid
    at OpenQA.Selenium.Remote.RemoteWebDriver.UnpackAndThrowOnError(Response errorResponse)
    at OpenQA.Selenium.Remote.RemoteWebDriver.Execute(String driverCommandToExecute, Dictionary`2 parameters)
    at OpenQA.Selenium.Remote.RemoteWebDriver.InternalExecute(String driverCommandToExecute, Dictionary`2 parameters)
    at OpenQA.Selenium.Remote.RemoteWebElement.Execute(String commandToExecute, Dictionary`2 parameters)
    at OpenQA.Selenium.Remote.RemoteWebElement.get_Text()

以下是此错误的屏幕截图:

Answer 1

好吧，您的问题来自问题类别，如何从下拉列表中选择一个选项。我通常使用两种方法:
方法 1 (使用操作生成器，高级用户操作 api):

WebElement mnuElement;
WebElement submnuElement;
mnEle = driver.findElement(By.Id("mnEle")).click();
sbEle = driver.findElement(By.Id("sbEle")).click();

Actions builder = new Actions(driver);
// Move cursor to the Main Menu Element
builder.MoveToElement(mnEle).perform();
// Giving 5 Secs for submenu to be displayed
Thread.sleep(5000L);
// Clicking on the Hidden SubMenu
driver.findElement(By.Id("sbEle")).click()

;
您可以获得的一些附加信息 here

第二种方法(直接使用js):

String cssSelector =..blablabla...
JavascriptExecutor js = (JavascriptExecutor) driver;
        StringBuilder stringBuilder = new StringBuilder();
        stringBuilder.append("var x = $(\'"+cssSelector+"\');");
        stringBuilder.append("x.click();");
        js.executeScript(stringBuilder.toString());

希望这对你有用)