ConcurrentQueue<T> example

gistfile1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Collections.Concurrent;
using System.Threading;
using System.Threading.Tasks;

namespace QueueTest
{
    public partial class Form1 : Form
    {
        private const int MonitorSleepLength = 10000;
        private ConcurrentQueue<string> _queue = new ConcurrentQueue<string>();

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            StartThreads();
        }

        private string randomString(int len = 10)
        {
            var rnd = new Random();
            var res = "";

            for (int i = 0; i < len; i++)
            {
                int chr;

                res += rnd.Next(0,1) == 0 ? (char) rnd.Next(65,90) : rnd.Next(97, 122);
            }

            return res;
        }

        private void StartThreads()
        {
            Action populateQueue = () =>
            {
                while (true)
                {
                    //Add a new string to the queue, then sleep for a random period of time (1-50ms)
                    var rnd = new Random();
                    var sleep = rnd.Next(1, 50);
                    var s = randomString();
                    _queue.Enqueue(s);

                    Console.WriteLine("populateQueue: Added '" + s + "', sleeping for " + sleep.ToString());

                    Thread.Sleep(sleep);
                }
            };

            Action processQueue = () =>
            {
                while (true)
                {
                    try
                    {
                        //Read the next item out of the queue

                        //1 in 10 change of sleeping for 10 seconds before trying to dequeue again
                        var rnd = new Random();
                        if (rnd.Next(1, 10) == 5)
                        {
                            Console.WriteLine("processQueue: Sleeping for 10 seconds."); 
                            Thread.Sleep(10 * 1000);
                        }

                        var s = "";

                        _queue.TryDequeue(out s);

                        if (!string.IsNullOrEmpty(s))
                        {
                            Console.WriteLine("processQueue: Dequeued '" + s + "'");
                        }
                    }
                    catch (Exception e)
                    {
                        Console.WriteLine("Error in processQueue: " + e.Message);
                    }
                }
            };

            Action monitorQueue = () =>
            {
                //Periodically output the current state of the queue
                while (true)
                {
                    Console.Write("monitorQueue: Queue has " + _queue.Count + " items.");
                    Thread.Sleep(MonitorSleepLength);
                }
            };

            Parallel.Invoke(populateQueue, processQueue, monitorQueue);
        }
    }
}