使用Nuget，C# Selenium WebDriver GetAttribute无法工作。

Question

我正试图用Selenium自动化一个网站，然而GetAttribute表现得很奇怪。无论我尝试getattributes的元素是什么，我都会得到下面的错误.我不知道为什么它会试图从System.IO中获取一些东西。

我隔离了代码，尝试使用IWebDriver和ChromeDriver，没有任何效果。

ChromeDriver chrome = new ChromeDriver(Util.Util.GetHomeDir() + "/eztools/drivers/");
chrome.Navigate().GoToUrl("https://dfe-portal.svrs.rs.gov.br/NFE/CCC");
Thread.Sleep(5000);
IWebElement el1 = chrome.FindElementById("CodUf");
Log.Debug("el1:" + el1);
Log.Debug("el2:" + el1.TagName);
Log.Debug("el2:" + el1.GetAttribute("data-val"));

错误。

em System.IO.Path.NormalizePath(String path, Boolean fullCheck, Int32 maxPathLength, Boolean expandShortPaths)
   em System.IO.Path.InternalGetDirectoryName(String path)
   em OpenQA.Selenium.Internal.FileUtilities.GetCurrentDirectory()
   em OpenQA.Selenium.Internal.ResourceUtilities.GetResourceStream(String fileName, String resourceId)
   em OpenQA.Selenium.Remote.RemoteWebElement.GetAtom(String atomResourceName)
   em OpenQA.Selenium.Remote.RemoteWebElement.GetAttribute(String attributeName)
   em ezrpa_runner.Cmds.Logic.WebCaptcha.run(CommandDomain cmd) na C:\ez\vs2019\ez-inspect\ezrpa-runner\Cmds\Web\WebCaptcha.cs:linha 44

Answer 1

所需的元素是一个动态元素，所以要定位元素，你必须诱使 WebDriverWait 与 预期条件 设为 ElementToBeClickable() 您可以使用以下任何一种方式 定位策略:

• 使用 身份证:

  //IWebElement el1 = new WebDriverWait(driver, TimeSpan.FromSeconds(20)).Until(ExpectedConditions.ElementToBeClickable(By.Id("CodUf")));
  //Incase you are using Nuget
  IWebElement el1 = new WebDriverWait(driver, TimeSpan.FromSeconds(10)).Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementToBeClickable(By.Id("CodUf")));
  Log.Debug("el1:" + el1);
  Log.Debug("el2:" + el1.TagName);
  Log.Debug("el2:" + el1.GetAttribute("data-val"));
  

• 使用 名称:

  //IWebElement el1 = new WebDriverWait(driver, TimeSpan.FromSeconds(20)).Until(ExpectedConditions.ElementToBeClickable(By.Name("CodUf")));
  //Incase you are using Nuget
  IWebElement el1 = new WebDriverWait(driver, TimeSpan.FromSeconds(10)).Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementToBeClickable(By.Name("CodUf")));
  Log.Debug("el1:" + el1);
  Log.Debug("el2:" + el1.TagName);
  Log.Debug("el2:" + el1.GetAttribute("data-val"));
  

• 使用 CssSelector:

  //IWebElement el1 = new WebDriverWait(driver, TimeSpan.FromSeconds(20)).Until(ExpectedConditions.ElementToBeClickable(By.CssSelector("select[name='CodUf']")));
  //Incase you are using Nuget
  IWebElement el1 = new WebDriverWait(driver, TimeSpan.FromSeconds(10)).Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementToBeClickable(By.CssSelector("select[name='CodUf']")));
  Log.Debug("el1:" + el1);
  Log.Debug("el2:" + el1.TagName);
  Log.Debug("el2:" + el1.GetAttribute("data-val"));
  

• 使用 XPath:

  //IWebElement el1 = new WebDriverWait(driver, TimeSpan.FromSeconds(20)).Until(ExpectedConditions.ElementToBeClickable(By.XPath("//select[@name='CodUf']")));
  //Incase you are using Nuget
  IWebElement el1 = new WebDriverWait(driver, TimeSpan.FromSeconds(10)).Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementToBeClickable(By.XPath("//select[@name='CodUf']")));
  Log.Debug("el1:" + el1);
  Log.Debug("el2:" + el1.TagName);
  Log.Debug("el2:" + el1.GetAttribute("data-val"));
  

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参考资料

你可以在.ExpectedConditions.ElementIsVisible中找到相关讨论。

• ExpectedConditions.ElementIsVisible即使元素存在也会返回超时异常。