Add code examples, and documentation

patterns/state/WithStatePattern/States/Off.cs

@@ -0,0 +1,14 @@
+namespace WithStatePattern.States;
+
+public class Off : State
+{
+   public Off(Car car)
+      : base(car) { }
+
+   public override void TurnKeyClockwise()
+   {
+      Console.WriteLine("The engine has started");
+      Console.WriteLine();
+      _car.ChangeState(new Stopped(_car));
+   }
+}