Beispiel #1
0
        /// <summary>
        ///
        /// </summary>
        public async void LoadDataIntoSharedDomainModelAsync()
        {
            var myDataCollection = await SomeStatelessService.LongRunningGetDataMethodAsync();

            // write-access to resources must be locked to be thread-safe! - Even simple assignments like "_a = 2".
            // Do only lock your classes' own resources.
            // Try not to call any other objects's method inside of the lock in order to prevent deadlocks (except side effect free ones).

            /*
             * Sometimes a shared resource is only written in one thread but read in multiple threads.
             * An example could be a data cache that is filled by one "data load task" and that is used by multiple threads.
             * Or image a queue of workItems that are processed by multiple workers.
             *
             * see http://www.nullskull.com/a/1464/producerconsumer-queue-and-blockingcollection-in-c-40.aspx):
             * System.Collections.Concurrent.IProducerConsumerCollection<T>
             *  System.Collections.Concurrent.ConcurrentBag<T>
             *  System.Collections.Concurrent.ConcurrentQueue<T>
             *  System.Collections.Concurrent.ConcurrentStack<T>
             *
             *  System.Collections.Concurrent.BlockingCollection<T>
             *      System.Collections.Concurrent.ConcurrentDictionary<T>
             */

            // => see "producer-consumer" pattern and reader/writer locks.

            // Don't use:
            // Monitor, Mutex, Semaphore, Pulse-Method, manualResetEvent, ThreadPool. cancellatioins etc. pp

            // Remark: When reading from the collection, you'll have to catch an exception that occurs if the list is changed during enumeration!
            lock (_loadedObjectsOfThisWorkItemContext)
            {
                LoadedObjectsOfThisWorkItemContext.AddRange(myDataCollection);
            }
        }
        /// <summary>
        ///
        /// </summary>
        public async void LoadDataIntoSharedDomainModelAsync()
        {
            var myDataCollection = await SomeStatelessService.LongRunningGetDataMethodAsync();

            // write-access to resources must be thread-safe!
            lock (this)
            {
                ReferencedObjectsCollection.AddRange(myDataCollection);
            }
        }