Multithreading in C#

A comprehensive guide on how to implement multithreading in C# to make better use of CPU resources and enhance application performance by executing multiple tasks simultaneously.

This article introduces how to create and manage threads in C# using Thread and Task. We will walk through examples that help you understand how to apply multithreading in your programming projects.

C# Code

using System;
using System.Threading;
using System.Threading.Tasks;

class Program
{
    // Method running on a separate thread
    static void PrintNumbers()
    {
        for (int i = 1; i <= 5; i++)
        {
            Console.WriteLine($"Number: {i}");
            Thread.Sleep(1000); // Pause for 1 second
        }
    }

    static async Task PrintNumbersAsync()
    {
        await Task.Run(() => PrintNumbers());
    }

    static void Main(string[] args)
    {
        Console.WriteLine("Starting multithreading...");

        // Create a new thread
        Thread thread = new Thread(PrintNumbers);
        thread.Start();

        // Use Task for asynchronous processing
        Task task = PrintNumbersAsync();
        
        // Wait for the thread to finish
        thread.Join();
        task.Wait();

        Console.WriteLine("Processing completed.");
    }
}

Detailed explanation:

1. PrintNumbers(): A method that runs on a separate thread, printing numbers from 1 to 5 with a 1-second pause between each print.
2. PrintNumbersAsync(): An asynchronous method using Task.Run to execute PrintNumbers.
3. Main():
   • Creates a new Thread and starts executing PrintNumbers.
   • Uses Task to run PrintNumbersAsync.
   • thread.Join(): Waits until the thread completes.
   • task.Wait(): Waits for the Task to complete.

System Requirements:

• C# 7.0 or newer
• .NET Core 2.1 or .NET Framework 4.5 and above

How to install the libraries needed to run the C# code above:

Install the .NET Core SDK from https://dotnet.microsoft.com/download.

Tips:

• Prefer using Task and async/await for easier thread management.
• Avoid creating too many simultaneous threads as it may degrade performance.

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