Thread signaling basics

Here is a custom-made console application example for you. Not really a good real world scenario, but the usage of thread signaling is there.

using System;using System.Threading;class Program{    static void Main()    {        bool isCompleted = false;        int diceRollResult = 0;        // AutoResetEvent is one type of the WaitHandle that you can use for signaling purpose.        AutoResetEvent waitHandle = new AutoResetEvent(false);        Thread thread = new Thread(delegate() {            Random random = new Random();            int numberOfTimesToLoop = random.Next(1, 10);            for (int i = 0; i < numberOfTimesToLoop - 1; i++) {                diceRollResult = random.Next(1, 6);                // Signal the waiting thread so that it knows the result is ready.                waitHandle.Set();                // Sleep so that the waiting thread have enough time to get the result properly - no race condition.                Thread.Sleep(1000);            }            diceRollResult = random.Next(1, 6);            isCompleted = true;            // Signal the waiting thread so that it knows the result is ready.            waitHandle.Set();        });        thread.Start();        while (!isCompleted) {            // Wait for signal from the dice rolling thread.            waitHandle.WaitOne();            Console.WriteLine("Dice roll result: {0}", diceRollResult);        }        Console.Write("Dice roll completed. Press any key to quit...");        Console.ReadKey(true);    }}

The way this works in a nutshell.

1. AutoResetEvent waitHandle = new AutoResetEvent(false); --- The false means that that wait handle is unsignaled if a waitHandle.WaitOne() is called it will stop the thread.

2. The thread you want to wait for another event to complete addwaitHandle.WaitOne();

3. In the thread that needs to be completed,at the end when completed addwaitHandle.Set();

waitHandle.WaitOne(); Waits for signal

waitHandle.Set(); signals completion.

For understanding concepts like signaling, see Thread Synchronization which would be a good place to start.

It's got examples too. You can then drill down into specific .net types based on what you're trying to do.. signal between threads within a process or across processes etc..