Response to http://www.paulstack.co.uk/blog/post/my-approach-to-refactoring-a-monster-switch-statement.aspx

TaskExecutor.cs

    public class TaskExecutor
    {
        private ITaskProcessor _processor;
        public TaskExecutor(ITaskProcessor processor)
        {
            _processor = processor;
        }

        public void DoTask()
        {
            SqlConnection oSqlConn = new SqlConnection();
            List<ScheduledTask> tasksToPerform = oSqlConn.GetTasks();

            try
            {
                foreach (ScheduledTask task in tasksToPerform)
                {
                    _processor.ProcessTask(task);
                }
            }
            catch (Exception ex)
            {
                OTLogger.LogGenericError(ex);
            }
            finally
            {
                SQLConnectionHelper.CloseConnection(oSqlConn);
            }
        }
    }

    public interface ITaskProcessor
    {
        void ProcessTask(ScheduledTask task);
    }

    public class TaskProcessor
    {
        private readonly Dictionary<string, Runner> _runners
        {
            get
            {
                return new Dictionary<string, Runner>
                           {
                               {"Task1", RunTask1},
                               {"Task2", RunTask2},
                               {"Task3", RunTask3},
                               {"Task4", RunTask4}
                           };
            }
        }

        public void ProcessTask(ScheduledTask task)
        {
            Runner runner;
            if (_runners.TryGetValue(task.Name, out runner))
            {
                runner.Run(task);
            }
        }
    }

    public abstract class Runner
    {
        public void Run(ScheduledTask task)
        {
            try
            {
                DoTask(task);
                task.LastRunTime = DateTime.UtcNow;
                UpdateTaskRunStatus(TaskStatus.Good, task);
            }
            catch (Exception ex)
            {
                UpdateTaskRunStatus(TaskStatus.Error, task);
                Logger.LogError("Error details here");
            }
        }

        protected abstract void DoTask(ScheduledTask task);
    }

    public class Task1Runner : Runner
    {
        protected override void DoTask(ScheduledTask task)
        {
            var task1Class = new Task1Class();
            task1Class.ExtractTop10Data(task.LastRunTime);
        }
    }

    public class Task2Runner : Runner
    {
        protected override void DoTask(ScheduledTask task)
        {
            var task2Class = new Task2Class();
            task2Class.CreateImageFeed();
        }
    }

    public class Task3Runner : Runner
    {
        protected override void DoTask(ScheduledTask task)
        {
            vr task3Class = new Task3Class();
            task3Class.DestroyImageFeed();
        }
    }

    public class Task4Runner : Runner
    {
        protected override void DoTask(ScheduledTask task)
        {
            var task4Class = new Task4Class();
            task4Class.ProcessData();
        }
    }