c# - How can I assign a name to a task in TPL

Question

I'm going to use lots of tasks running on my application. Each bunch of tasks is running for some reason. I would like to name these tasks so when I watch the Parallel Tasks window, I could recognize them easily.

With another point of view, consider I'm using tasks at the framework level to populate a list. A developer that use my framework is also using tasks for her job. If she looks at the Parallel Tasks Window she will find some tasks having no idea about. I want to name tasks so she can distinguish the framework tasks from her tasks.

It would be very convenient if there was such API:

var task = new Task(action, "Growth calculation task")

or maybe:

var task = Task.Factory.StartNew(action, "Populating the datagrid")

or even while working with Parallel.ForEach

Parallel.ForEach(list, action, "Salary Calculation Task"

Is it possible to name a task?

Is it possible to give ???Parallel.ForEach a naming structure (maybe using a lambda) so it creates tasks with that naming?

Is there such API somewhere that I'm missing?

---

I've also tried to use an inherited task to override it's ToString(). But unfortunately the Parallel Tasks window doesn't use ToString()!

class NamedTask : Task
{
    private string TaskName { get; set; }
    public NamedTask(Action action, string taskName):base(action)
    {
        TaskName = taskName;
    }

    public override string ToString()
    {
        return TaskName;
    }
}

Answer 1

You could relate any object with any object. Here is an extension for Task. It uses a WeakReference so the task can still be garbage collected when all references are out of scope.

Usage:

var myTask = new Task(...
myTask.Tag("The name here");
var nameOfTask = (string)myTask.Tag();

Extension class:

public static class TaskExtensions
{
    private static readonly Dictionary<WeakReference<Task>, object> TaskNames = new Dictionary<WeakReference<Task>, object>(); 

    public static void Tag(this Task pTask, object pTag)
    {
        if (pTask == null) return;
        var weakReference = ContainsTask(pTask);
        if (weakReference == null)
        {
            weakReference = new WeakReference<Task>(pTask);
        }
        TaskNames[weakReference] = pTag;
    }

    public static object Tag(this Task pTask)
    {
        var weakReference = ContainsTask(pTask);
        if (weakReference == null) return null;
        return TaskNames[weakReference];
    }

    private static WeakReference<Task> ContainsTask(Task pTask)
    {
        foreach (var kvp in TaskNames.ToList())
        {
            var weakReference = kvp.Key;

            Task taskFromReference;
            if (!weakReference.TryGetTarget(out taskFromReference))
            {
                TaskNames.Remove(weakReference); //Keep the dictionary clean.
                continue;
            }

            if (pTask == taskFromReference)
            {
                return weakReference;
            }
        }
        return null;
    }
}