DZone Snippets: thread code

Interprocess synchronization (safe threading)

mstampar (Miroslav Stampar) — Wed, 02 May 2007 21:20:27 GMT

Three ways for safe threading:



using System;

using System.Collections.Generic;

using System.Text;

using System.Threading;



namespace ConsoleApplication12

{

    class Program

    {

        static object thisLock = new object();

        static int z = 0;

        private static void ThrStart()

        {

            for (int i = 0; i < 10000; i++)

            {

                lock (thisLock)

                {

                    z++;

                    Console.WriteLine(z);

                }

            }

        }



        private static void ThrStart2()

        {

            for (int i = 0; i < 10000; i++)

            {

                Monitor.Enter(thisLock);

                z++;

                Console.WriteLine(z);

                Monitor.Exit(thisLock);

            }

        }



        static Mutex mutex = new Mutex();

        private static void ThrStart3()

        {

            for (int i = 0; i < 10000; i++)

            {

                mutex.WaitOne();

                z++;

                Console.WriteLine(z);

                mutex.ReleaseMutex();

            }

        }





        static void Main(string[] args)

        {

            Thread t1 = new Thread(new ThreadStart(ThrStart));

            Thread t2 = new Thread(new ThreadStart(ThrStart));

            t1.Start();

            t2.Start();

            t1.Join();

            t2.Join();



            t1 = new Thread(new ThreadStart(ThrStart2));

            t2 = new Thread(new ThreadStart(ThrStart2));

            t1.Start();

            t2.Start();

            t1.Join();

            t2.Join();



            t1 = new Thread(new ThreadStart(ThrStart3));

            t2 = new Thread(new ThreadStart(ThrStart3));

            t1.Start();

            t2.Start();

            t1.Join();

            t2.Join();

        }

    }

}

Parametrized thread start

mstampar (Miroslav Stampar) — Tue, 24 Apr 2007 22:39:31 GMT



   Thread t = new Thread (new ParameterizedThreadStart(FetchUrl));

    t.Start (www.google.com);

 

....

 

static void FetchUrl(object _url)

{

    string url = (string)_url;

}

Safe update of windows control from other threads

mstampar (Miroslav Stampar) — Tue, 24 Apr 2007 22:38:09 GMT



        delegate void UpdateReportCallback(string text);

        private void UpdateReport(string message)

        {

            // InvokeRequired required compares the thread ID of the

            // calling thread to the thread ID of the creating thread.

            // If these threads are different, it returns true.

            if (this.textBoxReport.InvokeRequired)

            {

                UpdateReportCallback d = new UpdateReportCallback(UpdateReport);

                this.Invoke(d, new object[] { message });

            }

            else

            {

                textBoxReport.Text = message + System.Environment.NewLine + textBoxReport.Text;

            }

        }