How can I take a screenshot with Selenium WebDriver?

Question

Is it possible to take a screenshot using Selenium WebDriver?

(Note: Not Selenium Remote Control)

Answer 1

C#

public static void TakeScreenshot(IWebDriver driver, String filename)
{
    // Take a screenshot and save it to filename
    Screenshot screenshot = ((ITakesScreenshot)driver).GetScreenshot();
    screenshot.SaveAsFile(filename, ImageFormat.Png);
}