C# : Invoke a method with [Type].InvokeMember() in a separate Thread

Question

I am using this code where I am invoking the run method of a List of classes that I loaded dynamically from dlls:

for (int i = 0; i < robotList.Count; i++)
{
    Type t = robotList[i]; //robotList is a List<Type>
    object o = Activator.CreateInstance(t);
    t.InvokeMember("run", BindingFlags.Default | BindingFlags.InvokeMethod, null, o, null);
}

The invokeMember is invoking the run methodof each of the classes in the list.

Now how can I invoke this run method from invokeMember in a separate Thread ? So that I'll have separate threads running for each of the invoked methods.

Answer 1

If you know that all your dynamically loaded types implement Run, could you just require they all implement IRunable and get rid of the reflection part?

Type t = robotList[i];
IRunable o = Activator.CreateInstance(t) as IRunable;
if (o != null)
{
    o.Run(); //do this in another thread of course, see below
}

If not, this will work:

for (int i = 0; i < robotList.Count; i++)
{
    Type t = robotList[i];
    object o = Activator.CreateInstance(t);
    Thread thread = new Thread(delegate()
    {
        t.InvokeMember("Run", BindingFlags.Default | BindingFlags.InvokeMethod, null, o, null);
    });
    thread.Start();
}

Answer 2

Have a look at this sample for one way of doing it:

using System;
using System.Threading;
using System.Reflection;
using System.Collections.Generic;

namespace Obfuscation
{
    public class Program
    {
        static Type[] robotArray = new Type[] { typeof(Program) };
        static List<Type> robotList = new List<Type>(robotArray);

        internal void Run()
        {
            Console.WriteLine("Do stuff here");
        }

        internal static void RunInstance(object threadParam)
        {
            Type t = (Type)threadParam;
            object o = Activator.CreateInstance((Type)t);
            t.InvokeMember("Run", BindingFlags.InvokeMethod | BindingFlags.Instance | BindingFlags.NonPublic, null, o, null);
        }

        public static void Main(string[] args)
        {
            for (int i = 0; i < robotList.Count; i++)
            {
                ThreadPool.QueueUserWorkItem(new WaitCallback(RunInstance), robotList[i]);
            }
        }
    }
}

Answer 3

Hi,

I was wandering in the answer provided above:

   Thread thread = new Thread(delegate()
    {
        t.InvokeMember("Run", BindingFlags.Default | BindingFlags.InvokeMethod, null, o, null);
    });

If we assume for a second that "run" returns a bool, for instance. How do you get back that bool value from the thread?

Thanks