TaskCompleteSource example

Run TaskCompleteSource.cs

        [Fact]
        public void RunTaskCompleteSourceTest()
        {
            TaskCompletionSource<FileInfo> taskCompletionSource = new TaskCompletionSource<FileInfo>();
            Task<FileInfo> anotherTask = taskCompletionSource.Task;

            Task fetchFileTask = Task.Factory.StartNew(()=>{
                FileInfo fileInfo = new FileInfo(Directory.GetFiles(Environment.CurrentDirectory)[0]);
                taskCompletionSource.SetResult(fileInfo);

                // Releasing the anotherTask.Result also be done by calling SetException or SetCancel
                //taskCompletionSource.SetException(new InvalidOperationException("this action is illegal"));

                // Will raise a TaskCanceledException since the task was canceled.
                //taskCompletionSource.SetCanceled();
            });

            Task accessFileTask = Task.Factory.StartNew(() =>
            {
                // Calling the Result property is a blocking call; the thread continues after assigning the Result object, 
                // receiving an exception, or canceling the task.
                FileInfo info = anotherTask.Result;
                Trace.WriteLine($"Received file '{info.Name}, last modified {info.LastWriteTime}'");

                // TODO: do something with the file
            });

            // Avoid exiting the test method before both tasks have finished
            Task.WaitAll(fetchFileTask, accessFileTask);
        }