Selenium c# Webdriver: Wait Until Element is Present

General Discussions
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#1

I want to make sure that an element is present before the webdriver starts doing stuff.

I’m trying to get something like this to work:

WebDriverWait wait = new WebDriverWait(driver, new TimeSpan(0,0,5));
wait.Until(By.Id("login"));

I’m mainly struggling how to setup up the anynomous function…

#2

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 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 straight-forward:

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();