Esempio n. 1
0
        public static void ListExample()
        {
            var list = new List <int>();

            for (int i = 0; i < 1000; i++)
            {
                list.Add(i);
            }

            int    count    = 0;
            object countLck = new object();

            // Object to box counter
            BoxedInt countObj = new BoxedInt
            {
                Counter = 0
            };

            Parallel.ForEach(list, (item) =>
            {
                Console.WriteLine($"I am working on item {item}");

                // Atomically increment count....
                Interlocked.Increment(ref count);

                // .. or do it with locks, to isolate a critical section
                lock (countLck) // An object is required here.
                {
                    count++;
                }

                // Typically, you lock the entire object, if possible
                // we previously used 'count', which is _not_ an object
                lock (countObj)
                {
                    countObj.Counter++;
                }
            });

            Console.WriteLine($"count now is {count}");
            Console.WriteLine($"countObj.Count now is {countObj.Counter}");
        }
Esempio n. 2
0
        public static void ArrayExample()
        {
            const int size = 4;

            int [] A = new int[size];

            for (int i = 0; i < size; i++)
            {
                A[i] = i;
            }

            for (int i = 0; i < size; i++)
            {
                Console.WriteLine($"A[{i}] is {A[i]}");
            }

            Parallel.ForEach(A, (item) =>
            {
                item *= 2;
                Console.WriteLine($"item now is {item}");
            });

            for (int i = 0; i < size; i++)
            {
                Console.WriteLine($"A[{i}] is {A[i]}");
            }

            var boxedList = BoxedInt.CreateList(A);

            Parallel.ForEach(boxedList, (item) =>
            {
                item.Counter *= 2;
            });

            foreach (var i in boxedList)
            {
                Console.WriteLine(i);
            }
        }