using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
namespace ParallelInvokeMethods
{
    class DataParallelism
    {
        static void Main(string[] args)
        {
            SynchronousProcess();
        }
        private static void PostData()
        {
            // Code to send data to  web API ( web service ).
            Thread.Sleep(60000);
        }
        private static void SynchronousProcess()
        {
            Console.WriteLine("Syncronus Process Started");
            DateTime startTime = DateTime.Now;
            List<int> batchList = new List<int> { 1, 2, 3, 4, 5 };
            Console.WriteLine("Start Time:" + startTime);
            foreach (int item in batchList)
            {
                Console.WriteLine("Begin task..." + item);
                PostData();
                Console.WriteLine("End task..." + item);
            }
            DateTime endTime = DateTime.Now;
            Console.WriteLine("End Time:" + endTime);
            TimeSpan timeExecution = endTime - startTime;
            Console.WriteLine("Total time execution :" + timeExecution);
            Console.WriteLine("Syncronus Process End");
        }
    }
}

Synchronous Process Started
    Start Time:5/30/2015 12:49:29 PM
    Begin task...1
    End task...1
    Begin task...2
    End task...2
    Begin task...3
    End task...3
    Begin task...4
    End task...4
    Begin task...5
    End task...5
    End Time:5/30/2015 12:54:29 PM
    Total time execution :00:05:00.0333292
Synchronous Process End

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
namespace ParallelInvokeMethods
{
    class DataParallelism
    {
        static void Main(string[] args)
        {
            ParallelProcess();        
        }
        private static void PostData()
        {
            // Code to send data to  web API ( web service ).
            Thread.Sleep(60000);
        }

        private static void ParallelProcess()
        {
            Console.WriteLine("Parallel Process Started");
            DateTime startTime = DateTime.Now;
            List<int> batchList = new List<int> { 1, 2, 3, 4, 5 };
            Console.WriteLine("Start Time:" + startTime);
            Parallel.ForEach(batchList, item =>
            {
               
                Console.WriteLine("Begin task..." + item);
                 PostData();
                Console.WriteLine("End task..." + item);
            });
            DateTime endTime = DateTime.Now;
            Console.WriteLine("End Time:" + endTime);
            TimeSpan timeExecution = endTime - startTime;
            Console.WriteLine("Total time execution :" + timeExecution);
            Console.WriteLine("Parallel Process End");
        }
    }
}