How to delay 'hot' tasks so they can processed in a set order

Question

Say I have a set of tasks:

        var task1 = DoThisAsync(...);
        var task2 = DoThatAsync(...);
        var task3 = DoOtherAsync(...);
        var tas         


        

Answer 1

Calling a method runs code. If you want an object that will call this method later, then use a delegate.

In this case, you could use Func<Task>, which is an asynchronous delegate. A list of these should suffice:

// Build the list of operations in order.
var operations = new List<Func<Task>>();
operations.Add(() => DoThisAsync(...));
operations.Add(() => DoThatAsync(...));
operations.Add(() => DoOtherAsync(...));

// Execute them all one at a time.
foreach (var operation in operations)
  await operation();

Answer 2

you can simply create tasks with its constructor and then, call execution with .Start() methods.

Here an example:

var taskList = InitQueue();
foreach (var t in taskList.OrderBy(i => i.Order))
{
    //Here I can skedule an existing task
    t.TaskToRun.Start();
    t.TaskToRun.Wait();
    Console.WriteLine($"Task {t.Order} has finished its job");
}


public class TaskQueue : List<TaskItem>
{
}

public class TaskItem
{
    public int Order { get; set; }
    public Task TaskToRun { get; set; }
}

private static TaskQueue InitQueue()
{
    var queue = new TaskQueue();
    queue.Add(new TaskItem
    {
        Order = 1,
        TaskToRun = new Task(() =>
        {
            Task.Delay(500);
            Console.WriteLine("Hello from task 1");
        })
    });
    queue.Add(new TaskItem
    {
        Order = 4,
        TaskToRun = new Task(() => Console.WriteLine("Hello from task 4"))
    });
    queue.Add(new TaskItem
    {
        Order = 3,
        TaskToRun = new Task(() =>
        {
            Task.Delay(5000);
            Console.WriteLine("Hello from task 3");
        })
    });
    queue.Add(new TaskItem
    {
        Order = 2,
        TaskToRun = new Task(() => Console.WriteLine("Hello from task 2"))
    });

    return queue;
}