Selenium C# WebDriver: Wait until element is present

Question

Using the solution provided by Mike Kwan may have an impact in overall testing performance, since the implicit wait will be used in all FindElement calls.

Many times you'll want the FindElement to fail right away when an element is not present (you're testing for a malformed page, missing elements, etc.). With the implicit wait these operations would wait for the whole timeout to expire before throwing the exception. The default implicit wait is set to 0 seconds.

I've written a little extension method to IWebDriver that adds a timeout (in seconds) parameter to the FindElement() method. It's quite self-explanatory:

public static class WebDriverExtensions
{
    public static IWebElement FindElement(this IWebDriver driver, By by, int timeoutInSeconds)
    {
        if (timeoutInSeconds > 0)
        {
            var wait = new WebDriverWait(driver, TimeSpan.FromSeconds(timeoutInSeconds));
            return wait.Until(drv => drv.FindElement(by));
        }
        return driver.FindElement(by);
    }
}

I didn't cache the WebDriverWait object as its creation is very cheap, this extension may be used simultaneously for different WebDriver objects, and I only do optimizations when ultimately needed.

Usage is straightforward:

var driver = new FirefoxDriver();
driver.Navigate().GoToUrl("http://localhost/mypage");
var btn = driver.FindElement(By.CssSelector("#login_button"));
btn.Click();
var employeeLabel = driver.FindElement(By.CssSelector("#VCC_VSL"), 10);
Assert.AreEqual("Employee", employeeLabel.Text);
driver.Close();

Alternatively you can use an implicit wait:

driver.Manage().Timeouts().ImplicitWait = TimeSpan.FromSeconds(10);

An implicit wait is to tell WebDriver to poll the DOM for a certain amount of time when trying to find an element or elements if they are not immediately available. The default setting is 0. Once set, the implicit wait is set for the life of the WebDriver object instance.

You can also use

ExpectedConditions.ElementExists

So you will search for an element availability like that

new WebDriverWait(driver, TimeSpan.FromSeconds(timeOut)).Until(ExpectedConditions.ElementExists((By.Id(login))));

Source

Here's a variation of Loudenvier's solution that also works for getting multiple elements:

public static class WebDriverExtensions
{
    public static IWebElement FindElement(this IWebDriver driver, By by, int timeoutInSeconds)
    {
        if (timeoutInSeconds > 0)
        {
            var wait = new WebDriverWait(driver, TimeSpan.FromSeconds(timeoutInSeconds));
            return wait.Until(drv => drv.FindElement(by));
        }
        return driver.FindElement(by);
    }

    public static ReadOnlyCollection<IWebElement> FindElements(this IWebDriver driver, By by, int timeoutInSeconds)
    {
        if (timeoutInSeconds > 0)
        {
            var wait = new WebDriverWait(driver, TimeSpan.FromSeconds(timeoutInSeconds));
            return wait.Until(drv => (drv.FindElements(by).Count > 0) ? drv.FindElements(by) : null);
        }
        return driver.FindElements(by);
    }
}

Inspired by Loudenvier's solution, here's an extension method that works for all ISearchContext objects, not just IWebDriver, which is a specialization of the former. This method also supports waiting until the element is displayed.

static class WebDriverExtensions
{
    /// <summary>
    /// Find an element, waiting until a timeout is reached if necessary.
    /// </summary>
    /// <param name="context">The search context.</param>
    /// <param name="by">Method to find elements.</param>
    /// <param name="timeout">How many seconds to wait.</param>
    /// <param name="displayed">Require the element to be displayed?</param>
    /// <returns>The found element.</returns>
    public static IWebElement FindElement(this ISearchContext context, By by, uint timeout, bool displayed=false)
    {
        var wait = new DefaultWait<ISearchContext>(context);
        wait.Timeout = TimeSpan.FromSeconds(timeout);
        wait.IgnoreExceptionTypes(typeof(NoSuchElementException));
        return wait.Until(ctx => {
            var elem = ctx.FindElement(by);
            if (displayed && !elem.Displayed)
                return null;

            return elem;
        });
    }
}

Example usage:

var driver = new FirefoxDriver();
driver.Navigate().GoToUrl("http://localhost");
var main = driver.FindElement(By.Id("main"));
var btn = main.FindElement(By.Id("button"));
btn.Click();
var dialog = main.FindElement(By.Id("dialog"), 5, displayed: true);
Assert.AreEqual("My Dialog", dialog.Text);
driver.Close();

I confused an anonymous function with a predicate. Here's a little helper method:

   WebDriverWait wait;
    private void waitForById(string id)
    {
        if (wait == null)
            wait = new WebDriverWait(driver, new TimeSpan(0, 0, 5));

        //wait.Until(driver);
        wait.Until(d => d.FindElement(By.Id(id)));
    }

You can find out something like this in C#.

This is what I used in JUnit - Selenium

WebDriverWait wait = new WebDriverWait(driver, 100);
WebElement element = wait.until(ExpectedConditions.elementToBeClickable(By.id("submit")));

Do import related packages.