How do I use Semaphore in C#?

How do I use Semaphore in C#?

You can use the Semaphore class in C# to control access to a resource across multiple threads. Would you like a code example?

Yes, please provide a code example.

Here's a simple example:

using System;
using System.Threading;

class Program
{
    static Semaphore semaphore = new Semaphore(2, 2);

    static void Main()
    {
        for (int i = 0; i < 5; i++)
        {
            Thread t = new Thread(AccessResource);
            t.Start(i);
        }
    }

    static void AccessResource(object id)
    {
        Console.WriteLine($"Thread {id} is waiting to access the resource...");
        semaphore.WaitOne(); // Wait until it is safe to enter
        Console.WriteLine($"Thread {id} has entered the resource.");
        Thread.Sleep(2000); // Simulate some work
        Console.WriteLine($"Thread {id} is leaving the resource.");
        semaphore.Release(); // Release the semaphore
    }
}

This code allows up to 2 threads to access the resource simultaneously.

What does the WaitOne method do?

The WaitOne method blocks the current thread until it is able to enter the semaphore, ensuring that the maximum number of threads accessing the resource is not exceeded.