使用“ExpectedConditions”等待验证不起作用

Question

UPDATED VERSION

I'm trying to find a more dynamic way to wait for elements instead of using static wait functions like Task.Event(2000).Wait();

The solution to this seems to be this:

WebDriverWait wait = new WebDriverWait(driver, TimeSpan.FromSeconds(30));
    wait.Until(ExpectedConditions.ElementToBeClickable(By.XPath("//div[2]/div/input")));

But when I use this function, the "ExpectedConditions" always lights up red indicating that it: "does not exist in the current context".

I've placed the function in one of my testcases:

(I am using C#/Visual Studios, Project type: Classlibrary)

using NUnit.Framework;
using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;
using OpenQA.Selenium.Firefox;
using OpenQA.Selenium.Support.UI;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

    namespace ClassLibrary1
    {
        public class MyFirstTest
        {
            IWebDriver driver = new FirefoxDriver();

            [Test]
            public void WaitverifyTest()
            {
                driver.Navigate().GoToUrl("https://www.google.se/");
                driver.Manage().Window.Maximize();

                Task.Delay(4000).Wait();

                driver.FindElement(By.XPath("//div[2]/div/input")).SendKeys("Selenium");

                WebDriverWait wait = new WebDriverWait(driver, TimeSpan.FromSeconds(10));
                IWebElement element = wait.Until(ExpectedConditions.ElementToBeClickable(By.XPath("//div[2]/div/input")));
                element.Click();

                driver.FindElement(By.XPath("//center/input")).Click();
            }
       }
   }

(The xpath is a location type xpath, it is valid and works in both Selenium IDE and in Visual Studios.)

Anyone has any idea what I'm doing wrong?

I have two suspicions:

1. My version of selenium could be too new (3.6.0.0)

According to selenium.io , ExpectedCondition was last updated in 3.1.0. Maybe it is no longer vaild. Is there someway to check this?

2. Maybe my project type is not compatible with ExpectedCondition, and therefore does not recognize it?

Answer 1

I've seen this before.

Make sure you've installed both the Selenium.Webdriver and Selenium.Support NuGet packages for your project. You'll need the Selenium.Support package to use ExpectedConditions.

Answer 2

I resloved this way:

1: Using nuget, search for DotNetSeleniumExtras.WaitHelpers,

2: Import that namespace into your class.

    using SeleniumExtras.WaitHelpers

3: Then run the following code:

    WebDriverWait wait = new WebDriverWait(driver, TimeSpan.FromSeconds(10));
    wait.Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementIsVisible(By.Id("element ID")));

Answer 3

I don't understand this line:

IWebElement element = wait.Until(ExpectedConditions.ElementToBeClickable(By.XPath("//div[2]/div/input")));

How are you able to cast Until to an IWebElement since it returns bool? I might be missing something.

But you might be able to bypass the error if you don't use ExpectedConditions, like so:

wait().Until( foo => driver.FindElement(By.XPath("//div[2]/div/input")).Enabled);

WebDriverWait takes as a parameter a function that returns a bool. You can create one within the parameters with the above code, that will return true when the element is enabled.

Answer 4

Instead of VisibilityOfAllElementsLocatedBy use elementTobeClickable method, it should work i guess

        WebDriverWait wait = new WebDriverWait(driver, TimeSpan.FromSeconds(30));

        driver.Navigate().GoToUrl("https://www.svt.se/");
        driver.Manage().Window.Maximize();

        wait.Until(ExpectedConditions.ElementToBeClickable(
        By.XPath("//li[4]/a")));

        driver.FindElement(By.XPath("//li[4]/a")).Click();