Support of progress reporting and incremental results in .NET 4.0 "Task Parallel Library"

.net-4.0, c#, task-parallel-library

Solution

This example updates a progress bar:

using System;   
using System.Threading;   
using System.Threading.Tasks;   
using System.Windows.Forms;   

class SimpleProgressBar : Form   
{   
    [STAThread]   
    static void Main(string[] args)   
    {   
        Application.EnableVisualStyles();   
        Application.Run(new SimpleProgressBar());   
    }   

    protected override void OnLoad(EventArgs e)   
    {   
        base.OnLoad(e);   

        int iterations = 100;   

        ProgressBar pb = new ProgressBar();   
        pb.Maximum = iterations;   
        pb.Dock = DockStyle.Fill;   
        Controls.Add(pb);   

        Task.ContinueWith(delegate   
        {   
            Parallel.For(0, iterations, i =>  
            {   
                Thread.SpinWait(50000000); // do work here   
                BeginInvoke((Action)delegate { pb.Value++; });   
            });   
        });   
    }   
}

Updating a progress bar from inside a Parallel.For

Problem

I know that Task Parallel Library is still in Beta and there are likely to be less resources available but from whatever I have read, library gives very special treatment to task scheduling, exception handling and cancellation. But I don't find any references to progress reporting and sending incremental results from tasks. These 2 things seem too important to ignore. Can you throw some light on how to handle these in Task Parallel Library or refer some articles which explains them?

Original source