[dotnet] Add screenshot support for EventFiringWebElement (#9258)

* Add screenshot support for EventFiringWebElement

* Add EventFiringWebElement screenshot test

Co-authored-by: Diego Molina <[email protected]>

Author: TroyWalshProf

dotnet/src/support/Events/EventFiringWebDriver.cs

@@ -1174,7 +1174,7 @@ public TimeSpan PageLoad
         /// <summary>
         /// EventFiringWebElement allows you to have access to specific items that are found on the page
         /// </summary>
-        private class EventFiringWebElement : IWebElement, IWrapsElement, IWrapsDriver
+        private class EventFiringWebElement : ITakesScreenshot, IWebElement, IWrapsElement, IWrapsDriver
         {
             private IWebElement underlyingElement;
             private EventFiringWebDriver parentDriver;
@@ -1566,6 +1566,23 @@ public ReadOnlyCollection<IWebElement> FindElements(By by)
                 return wrappedElementList.AsReadOnly();
             }
 
+            /// <summary>
+            /// Gets a <see cref="Screenshot"/> object representing the image of the page on the screen.
+            /// </summary>
+            /// <returns>A <see cref="Screenshot"/> object containing the image.</returns>
+            public Screenshot GetScreenshot()
+            {
+                ITakesScreenshot screenshotDriver = this.underlyingElement as ITakesScreenshot;
+                if (this.underlyingElement == null)
+                {
+                    throw new NotSupportedException("Underlying element instance does not support taking screenshots");
+                }
+
+                Screenshot screen = null;
+                screen = screenshotDriver.GetScreenshot();
+                return screen;
+            }
+
             /// <summary>
             /// Determines whether the specified <see cref="EventFiringWebElement"/> is equal to the current <see cref="EventFiringWebElement"/>. 
             /// </summary>

dotnet/test/support/Events/EventFiringWebDriverElementTest.cs

@@ -0,0 +1,24 @@
+using NUnit.Framework;
+
+namespace OpenQA.Selenium.Support.Events
+{
+    [TestFixture]
+    public class EventFiringWebDriverElementTest : DriverTestFixture
+    {
+        [SetUp]
+        public void Setup()
+        {
+            driver.Url = formsPage;
+        }
+
+        [Test]
+        public void CanTakeEventFiringWebElementScreenshot()
+        {
+            var firingDriver = new EventFiringWebDriver(driver);
+            IWebElement element = firingDriver.FindElement(By.Name("checky"));
+            Screenshot screenshot = ((ITakesScreenshot)element).GetScreenshot();
+
+            Assert.IsNotNull(screenshot);
+        }
+    }
+}