Question

I have a problem in Asp.net C#

I have the code below :
List objectList = new List();

foreach(var item in listItem)
{
  object obj = getData (item);
  objectList.add(obj);
}
Console.Write("Finish all");

Each time `getData (item);’ fires it takes about 1s;

I want all items in listItem to run at the same time and then execute after foreach finishes the Console.write("Finish all")

How can I do that?

Any idea will be appreciated!

Answer 1

        int itemCount = ItemList.Count;

             List<object> objectList = new List<object>();
            ManualResetEvent[] resetEvents = new ManualResetEvent[itemCount];

            for (int i = 0; i < itemCount; i++)
            {

                var item= ItemList[i];

                resetEvents[i] = new ManualResetEvent(false);
                ThreadPool.QueueUserWorkItem(new WaitCallback((object index) =>
                {
                    ItemCalEvent item = getData(item);

                    lock (objectList)
                        objectList.Add(item);

                    resetEvents[(int)index].Set();
                }), i);
            }
            WaitHandle.WaitAll(resetEvents);

This is good in .net 3.5