diff --git a/AMWD.Common.AspNetCore/Utilities/HtmlHelper.cs b/AMWD.Common.AspNetCore/Utilities/HtmlHelper.cs
new file mode 100644
index 0000000..1909e1a
--- /dev/null
+++ b/AMWD.Common.AspNetCore/Utilities/HtmlHelper.cs
@@ -0,0 +1,55 @@
+using System;
+using System.Linq;
+using System.Text.RegularExpressions;
+
+namespace AMWD.Common.AspNetCore.Utilities
+{
+	/// <summary>
+	/// Provides helpers for webpages.
+	/// </summary>
+	public static class HtmlHelper
+	{
+		/// <summary>
+		/// Checks whether a color is considered as dark.
+		/// </summary>
+		/// <param name="color">The color (hex or rgb - as defined in CSS)</param>
+		/// <returns><c>true</c> when the color is dark otherwise <c>false</c>.</returns>
+		public static bool IsDarkColor(string color)
+		{
+			if (string.IsNullOrWhiteSpace(color))
+				return false;
+
+			int r, g, b;
+
+			var rgbMatch = Regex.Match(color, @"^rgba?\(([0-9]+), ?([0-9]+), ?([0-9]+)");
+			var hexMatchFull = Regex.Match(color, @"^#?([0-9a-fA-F]{2})([0-9a-fA-F]{2})([0-9a-fA-F]{2})$");
+			var hexMatchLite = Regex.Match(color, @"^#?([0-9a-fA-F]{1})([0-9a-fA-F]{1})([0-9a-fA-F]{1})$");
+
+			if (rgbMatch.Success)
+			{
+				r = Convert.ToInt32(rgbMatch.Groups[1].Value);
+				g = Convert.ToInt32(rgbMatch.Groups[2].Value);
+				b = Convert.ToInt32(rgbMatch.Groups[3].Value);
+			}
+			else if (hexMatchFull.Success)
+			{
+				r = Convert.ToInt32(hexMatchFull.Groups[1].Value, 16);
+				g = Convert.ToInt32(hexMatchFull.Groups[2].Value, 16);
+				b = Convert.ToInt32(hexMatchFull.Groups[3].Value, 16);
+			}
+			else if (hexMatchLite.Success)
+			{
+				r = Convert.ToInt32(new string(hexMatchLite.Groups[1].Value.First(), 2), 16);
+				g = Convert.ToInt32(new string(hexMatchLite.Groups[2].Value.First(), 2), 16);
+				b = Convert.ToInt32(new string(hexMatchLite.Groups[3].Value.First(), 2), 16);
+			}
+			else
+			{
+				return false;
+			}
+
+			double luminance = (r * 0.299 + g * 0.587 + b * 0.114) / 255;
+			return luminance <= 0.5;
+		}
+	}
+}
diff --git a/AMWD.Common.Tests/Utilities/DelayedTaskTests.cs b/AMWD.Common.Tests/Utilities/DelayedTaskTests.cs
index 9cdce47..4bd8bbe 100644
--- a/AMWD.Common.Tests/Utilities/DelayedTaskTests.cs
+++ b/AMWD.Common.Tests/Utilities/DelayedTaskTests.cs
@@ -1,8 +1,8 @@
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
+using System.Diagnostics;
+using System.Threading;
 using System.Threading.Tasks;
+using AMWD.Common.Utilities;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
 
 namespace AMWD.Common.Tests.Utilities
@@ -11,6 +11,278 @@ namespace AMWD.Common.Tests.Utilities
 	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
 	public class DelayedTaskTests
 	{
-		// TODO
+		[TestMethod]
+		public void ShouldCreateNewDelayedTaskNotStarting()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTask = DelayedTask.Create(action, delay);
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(0, executionCount);
+		}
+
+		[TestMethod]
+		public void ShouldCreateNewDelayedTaskStarting()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTask = DelayedTask.Run(action, delay);
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+		}
+
+		[TestMethod]
+		public void ShouldRunOnceAfterReset()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTask = DelayedTask.Create(action, delay);
+			delayedTask.Reset();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+		}
+
+		[TestMethod]
+		public void ShouldCancelWaitingTask()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTask = DelayedTask.Run(action, delay);
+			delayedTask.Cancel();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(0, executionCount);
+		}
+
+		[TestMethod]
+		public async Task ShouldResetRunningDelay()
+		{
+			// arrange
+			int executionCount = 0;
+			var sw = new Stopwatch();
+
+			var delay = TimeSpan.FromMilliseconds(200);
+			var action = () => { sw.Stop(); executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			sw.Start();
+			var delayedTask = DelayedTask.Run(action, delay);
+			await Task.Delay(50);
+			delayedTask.Reset();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+			// delta of 50ms as the precision below 50ms is really bad for System.Timer
+			Assert.AreEqual(250, sw.ElapsedMilliseconds, 50);
+		}
+
+		[TestMethod]
+		public async Task ShouldNotExecutedImmediateOnCreated()
+		{
+			// arrange
+			int executionCount = 0;
+			var sw = new Stopwatch();
+
+			var delay = TimeSpan.FromMilliseconds(200);
+			var action = () => { sw.Stop(); executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			sw.Start();
+			var delayedTask = DelayedTask.Create(action, delay);
+			await Task.Delay(50);
+			bool isSuccess = delayedTask.ExecutePending();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+			sw.Stop();
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(0, executionCount);
+			// delta of 50ms as the precision below 50ms is really bad for System.Timer
+			Assert.AreEqual(1250, sw.ElapsedMilliseconds, 50);
+			Assert.IsFalse(isSuccess);
+		}
+
+		[TestMethod]
+		public async Task ShouldExecuteImmediateOnExecutePendingWhenRunning()
+		{
+			// arrange
+			int executionCount = 0;
+			var sw = new Stopwatch();
+
+			var delay = TimeSpan.FromMilliseconds(200);
+			var action = () => { sw.Stop(); executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			sw.Start();
+			var delayedTask = DelayedTask.Run(action, delay);
+			await Task.Delay(50);
+			bool isSuccess = delayedTask.ExecutePending();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+			// delta of 50ms as the precision below 50ms is really bad for System.Timer
+			Assert.AreEqual(50, sw.ElapsedMilliseconds, 50);
+			Assert.IsTrue(isSuccess);
+		}
+
+		[TestMethod]
+		public void ShouldReturnAnAwaiter()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+			var delayedTask = DelayedTask.Create(action, delay);
+
+			// act
+			delayedTask.Reset();
+			var awaiter = delayedTask.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.IsNotNull(awaiter);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+		}
+
+		[TestMethod]
+		public void ShouldHaveAnExceptionSet()
+		{
+			// arrange
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { throw new Exception("TEST :D"); };
+
+			// act
+			var delayedTask = DelayedTask.Run(action, delay);
+
+			var awaiter = delayedTask.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNotNull(delayedTask.Exception);
+		}
+
+		[TestMethod]
+		public void ShouldUseExceptionHandler()
+		{
+			// arrange
+			string exceptionText = null;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { throw new Exception("TEST :D"); };
+			var exceptionHandler = (Exception ex) =>
+			{
+				exceptionText = ex.Message;
+			};
+
+			// act
+			var delayedTask = DelayedTask.Run(action, delay)
+				.WithExceptionHandler(exceptionHandler);
+
+			var awaiter = delayedTask.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNotNull(delayedTask.Exception);
+			Assert.AreEqual("TEST :D", exceptionText);
+		}
+
+		[TestMethod]
+		public async Task ShouldReturnNormalTask()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+			var delayedTask = DelayedTask.Create(action, delay);
+
+			// act
+			delayedTask.Reset();
+			var task = delayedTask.Task;
+			await task;
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.IsNotNull(task);
+			Assert.IsInstanceOfType(task, typeof(Task));
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.AreEqual(1, executionCount);
+			Assert.AreEqual(TaskStatus.RanToCompletion, task.Status);
+		}
 	}
 }
diff --git a/AMWD.Common.Tests/Utilities/DelayedTaskWithResultTests.cs b/AMWD.Common.Tests/Utilities/DelayedTaskWithResultTests.cs
new file mode 100644
index 0000000..4e67d50
--- /dev/null
+++ b/AMWD.Common.Tests/Utilities/DelayedTaskWithResultTests.cs
@@ -0,0 +1,134 @@
+using System;
+using System.Diagnostics;
+using System.Threading;
+using System.Threading.Tasks;
+using AMWD.Common.Utilities;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace AMWD.Common.Tests.Utilities
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class DelayedTaskWithResultTests
+	{
+		[TestMethod]
+		public void ShouldCreateNewDelayedTaskNotStarting()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var function = () => { executionCount++; return new[] { 42, 21 }; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTaskWithResult = DelayedTask.Create(function, delay);
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.AreEqual(delay, delayedTaskWithResult.Delay);
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.IsNull(delayedTaskWithResult.Exception);
+			Assert.AreEqual(0, executionCount);
+		}
+
+		[TestMethod]
+		public async Task ShouldCreateNewDelayedTaskStarting()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var function = () => { executionCount++; return new[] { 42, 21 }; };
+
+			// act
+			var delayedTaskWithResult = DelayedTask.Run(function, delay);
+			int[] result = await delayedTaskWithResult;
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.AreEqual(delay, delayedTaskWithResult.Delay);
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.IsNull(delayedTaskWithResult.Exception);
+			Assert.AreEqual(1, executionCount);
+			CollectionAssert.AreEqual(new[] { 42, 21 }, result);
+		}
+
+		[TestMethod]
+		public void ShouldHaveAnExceptionSet()
+		{
+			// arrange
+			var delay = TimeSpan.FromMilliseconds(100);
+#pragma warning disable CS0162 // Unreachable Code detected.
+			var function = () => { throw new Exception("TEST :D"); return new[] { 42, 21 }; };
+#pragma warning restore CS0162 // Unreachable Code detected
+
+			// act
+			var delayedTaskWithResult = DelayedTask.Run(function, delay);
+
+			var awaiter = delayedTaskWithResult.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.IsNotNull(delayedTaskWithResult.Exception);
+		}
+
+		[TestMethod]
+		public void ShouldUseExceptionHandler()
+		{
+			// arrange
+			string exceptionText = null;
+			var delay = TimeSpan.FromMilliseconds(100);
+#pragma warning disable CS0162 // Unreachable Code detected.
+			var function = () => { throw new Exception("TEST :D"); return new[] { 42, 21 }; };
+#pragma warning restore CS0162 // Unreachable Code detected
+			var exceptionHandler = (Exception ex) =>
+			{
+				exceptionText = ex.Message;
+			};
+
+			// act
+			var delayedTaskWithResult = DelayedTask.Run(function, delay)
+				.WithExceptionHandler(exceptionHandler);
+
+			var awaiter = delayedTaskWithResult.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.IsNotNull(delayedTaskWithResult.Exception);
+			Assert.AreEqual("TEST :D", exceptionText);
+		}
+
+		[TestMethod]
+		public async Task ShouldReturnNormalTask()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var function = () => { executionCount++; return new[] { 42, 21 }; };
+			var delayedTaskWithResult = DelayedTask.Create(function, delay);
+
+			// act
+			delayedTaskWithResult.Reset();
+			var task = delayedTaskWithResult.Task;
+			int[] result = await task;
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.IsNotNull(task);
+			Assert.IsInstanceOfType(task, typeof(Task));
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.AreEqual(1, executionCount);
+			Assert.AreEqual(TaskStatus.RanToCompletion, task.Status);
+			CollectionAssert.AreEqual(new int[] { 42, 21 }, result);
+		}
+	}
+}
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0ab047f..8d04221 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,10 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased](https://git.am-wd.de/AM.WD/common/compare/v1.1.0...master)
 ### Added
 - CHANGELOG
+- `HtmlHelper.IsDarkColor` to classify a color as dark or light one (by luminance)
 
 ### Changed
 - Unit-Tests enhanced
-- Updated `NetRevisionTask`
+- Unit-Tests excluded from code coverage calcualtion
+- Updated NuGet package `NetRevisionTask`
 
 
 ## [v1.1.0](https://git.am-wd.de/AM.WD/common/compare/v1.0.2...v1.1.0) - 2021-11-22