C# - Are Parallel.Invoke and Parallel.ForEach essentially the same thing?

Parallel.ForEach goes through the list of elements and can perform some task on the elements of the array.

eg.

Parallel.ForEach(val, (array) => Sum(array));

Parallel.Invoke can invoke many functions in parallel.

eg.

Parallel.Invoke(
() => doSum(array),
() => doAvg(array),
() => doMedian(array));

As from the example above, you can see that they are different in functionality. ForEach iterates through a List of elements and performs one task on each element in parallel, while Invoke can perform many tasks in parallel on a single element.

Parallel.Invoke and Parallel.ForEach (when used to execute Actions) function the same, although yes one specifically wants the collection to be an Array. Consider the following sample:

List<Action> actionsList = new List<Action>
            {
                () => Console.WriteLine("0"),
                () => Console.WriteLine("1"),
                () => Console.WriteLine("2"),
                () => Console.WriteLine("3"),
                () => Console.WriteLine("4"),
                () => Console.WriteLine("5"),
                () => Console.WriteLine("6"),
                () => Console.WriteLine("7"),
                () => Console.WriteLine("8"),
                () => Console.WriteLine("9"),
            };

            Parallel.ForEach<Action>(actionsList, ( o => o() ));

            Console.WriteLine();

            Action[] actionsArray = new Action[]
            {
                () => Console.WriteLine("0"),
                () => Console.WriteLine("1"),
                () => Console.WriteLine("2"),
                () => Console.WriteLine("3"),
                () => Console.WriteLine("4"),
                () => Console.WriteLine("5"),
                () => Console.WriteLine("6"),
                () => Console.WriteLine("7"),
                () => Console.WriteLine("8"),
                () => Console.WriteLine("9"),
            };

            Parallel.Invoke(actionsArray);

            Console.ReadKey();

This code produces this output on one Run. It's output is generally in a different order every time.

0 5 1 6 2 7 3 8 4 9

0 1 2 4 5 6 7 8 9 3