[3.0/LINQ] Multi-threading in ForEach loop

[keitherb]

I have the following code in a console app:

foreach (string str in _betterStrings)
{
doSomething(str);
}

AddRangeButNoDuplicates(_betterStrings, _goodStrings);

I would like to add multi-threading, so that there is a CommandLine parameter which specifies the maximum threads, then spawns new threads which execute the doSomething(). As each thread completes, a new thread needs to be spawned, keeping the console app running at the maximum number of threads.

If there is anyone on this board that has done this, I would greatly appreciate it if you could point me in the best direction.

Thanks in advance.

[jmcilhinney]

I would suggest that you use the ThreadPool class to queue up your tasks and let the system worry about what's the optimum number to run simultaneously:

private static string[] _betterStrings;

static void Main(string[] args)
{
    foreach (string str in _betterStrings)
    {
        System.Threading.ThreadPool.QueueUserWorkItem(DoSomething, str);
    }
}

private static void DoSomething(object state)
{
    string str = state as string;

    // Use str here.
}

That will queue up an instance of DoSomething for each string in the array and each will be executed as a thread pool thread becomes available.