what is thread-local in c#

if you want to use local data in a thread and initialize it for each thread, you can use ThreadLocal<T> class, this class takes Delegate to a method that initializes the value.


class Program
    {

        public static ThreadLocal<int> _field = new ThreadLocal<int>(() => { return Thread.CurrentThread.ManagedThreadId; });

        static void Main(string[] args)
        {
            new Thread(() => {
                for (int i = 0; i < _field.Value; i++)
                {
                    Console.WriteLine("Thread A {0}",i);
                }
            }).Start();
            new Thread(() =>
            {
                for (int i = 0; i < _field.Value; i++)
                {
                    Console.WriteLine("Thread B {0}", i);
                }
            }).Start();
            Console.ReadKey();

            //Thread.CurrentThread gives the info of currewnt running Thread
        }
    }

Thread B 0

Thread A 0

Thread B 1

Thread A 1

Thread A 2

Thread B 2

Thread B 3