Limit the number of parallel threads in C#

Question

I am writing a C# program to generate and upload a half million files via FTP. I want to process 4 files in parallel since the machine have 4 cores and the file generating t

Answer 1

I have coded below technique where I use BlockingCollection as a thread count manager. It is quite simple to implement and handles the job. It simply accepts Task objects and add an integer value to blocking list, increasing running thread count by 1. When thread finishes, it dequeues the object and releases the block on add operation for upcoming tasks.

        public class BlockingTaskQueue
        {
            private BlockingCollection threadManager { get; set; } = null;
            public bool IsWorking
            {
                get
                {
                    return threadManager.Count > 0 ? true : false;
                }
            }

            public BlockingTaskQueue(int maxThread)
            {
                threadManager = new BlockingCollection(maxThread);
            }

            public async Task AddTask(Task task)
            {
                Task.Run(() =>
                {
                    Run(task);
                });
            }

            private bool Run(Task task)
            {
                try
                {
                    threadManager.Add(1);
                    task.Start();
                    task.Wait();
                    return true;

                }
                catch (Exception ex)
                {
                    return false;
                }
                finally
                {
                    threadManager.Take();
                }

            }

        }