C#. Threads and delegates

delegates gives functionality of creating additional threads…

examples

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;
using System.Runtime.Remoting.Messaging;

namespace SyncDelegateReview
{
    public delegate int BinaryOp(int x, int y);
    

    class Program
    {
        private static bool isDone = false;

        static void Main(string[] args)
        {
            //SyncCall();
            //ASyncCall();
            //ASyncCall2(); // works like annoying manager, always asks if additional thread isCompleted
            //ASyncCall3(); // works like annoying manager, always asks if additional thread isCompleted
            AsyncCallBackExample();

        }

        static int Add(int x, int y)
        {
            Console.WriteLine("Add() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId );
            Thread.Sleep(5000);
            return x+y;
        }

        static void SyncCall() // << blocks main thread
        {
            Console.WriteLine("*** Sync Delegate Review ***");
            Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

            BinaryOp b = new BinaryOp(Add);
            int answer = b(10, 10); // in main thread, sync mode...

            Console.WriteLine("Doing more work in Main()");
            Console.WriteLine("10 + 10 is {0}", answer);
            Console.ReadLine();
        }

        static void ASyncCall() // << blocks main thread
        {
            Console.WriteLine("*** ASync Delegate Review ***");
            Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

            BinaryOp b = new BinaryOp(Add);
            //int answer = b(10, 10); // in main thread, sync mode...
            IAsyncResult itf = b.BeginInvoke(10, 10, null, null);


               Console.WriteLine("Doing more work in Main()!");

            // getting result
            int answer = b.EndInvoke(itf);
            
            Console.WriteLine("10 + 10 is {0}", answer);
            Console.ReadLine();
        }


        static void ASyncCall2() // << allows work in main thread
        {
            Console.WriteLine("*** ASync Delegate Review ***");
            Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

            BinaryOp b = new BinaryOp(Add);
            //int answer = b(10, 10); // in main thread, sync mode...
            IAsyncResult itf = b.BeginInvoke(10, 10, null, null);


            while (!itf.IsCompleted) // always ask additional thread IsCompleted and works during this
            {
                Console.WriteLine("DoingMoreWorkInMain");
                Thread.Sleep(1000);
            }

            Console.WriteLine("Doing more work in Main()!");
            int answer = b.EndInvoke(itf);

            Console.WriteLine("10 + 10 is {0}", answer);
            Console.ReadLine();
        }


        static void ASyncCall3() // << allows work in main thread with max time limit
        {
            Console.WriteLine("*** ASync Delegate Review ***");
            Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

            BinaryOp b = new BinaryOp(Add);
            //int answer = b(10, 10); // in main thread, sync mode...
            IAsyncResult itf = b.BeginInvoke(10, 10, null, null);


            while (!itf.AsyncWaitHandle.WaitOne(1000,true)) //  max time to wait
                //always ask additional thread IsCompleted and works during this
            {
                Console.WriteLine("DoingMoreWorkInMain");
                Thread.Sleep(1000);
            }

            Console.WriteLine("Doing more work in Main()!");
            int answer = b.EndInvoke(itf);

            Console.WriteLine("10 + 10 is {0}", answer);
            Console.ReadLine();
        }

        static void AsyncCallBackExample()
        {
            Console.WriteLine("*** ASyncCallBackExample ***");
            Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

            BinaryOp b = new BinaryOp(Add);
            //int answer = b(10, 10); // in main thread, sync mode...
            IAsyncResult itf = b.BeginInvoke(
                10, // delegate param
                10, // delegate param
                new AsyncCallback(AddComplete), // CallBack method
                "Main() string object added to call back method"); // some object for call back method


            while (!isDone) //  
          
            {
                Console.WriteLine("DoingMoreWorkInMain");
                Thread.Sleep(1000);
            }

                    

           
            Console.ReadLine();
        }

        static void AddComplete(IAsyncResult itf)
        {
            Console.WriteLine("AddComplete() invoked on thread {0} ", Thread.CurrentThread.ManagedThreadId);
            AsyncResult ar = (AsyncResult)itf;
            BinaryOp b = (BinaryOp)ar.AsyncDelegate;
            string msg = (string)itf.AsyncState; // could be any object not only string...
            Console.WriteLine("10+10 is {0}",b.EndInvoke(itf));
            Console.WriteLine("message from Main " + msg);
            isDone = true;
        }


    }
}

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using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Threading;

using System.Runtime.Remoting.Messaging;

namespace SyncDelegateReview

{

public delegate int BinaryOp(int x, int y);

class Program

{

private static bool isDone = false;

static void Main(string[] args)

{

//SyncCall();

//ASyncCall();

//ASyncCall2(); // works like annoying manager, always asks if additional thread isCompleted

//ASyncCall3(); // works like annoying manager, always asks if additional thread isCompleted

AsyncCallBackExample();

}

static int Add(int x, int y)

{

Console.WriteLine("Add() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId );

Thread.Sleep(5000);

return x+y;

}

static void SyncCall() // << blocks main thread

{

Console.WriteLine("*** Sync Delegate Review ***");

Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

BinaryOp b = new BinaryOp(Add);

int answer = b(10, 10); // in main thread, sync mode...

Console.WriteLine("Doing more work in Main()");

Console.WriteLine("10 + 10 is {0}", answer);

Console.ReadLine();

}

static void ASyncCall() // << blocks main thread

{

Console.WriteLine("*** ASync Delegate Review ***");

Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

BinaryOp b = new BinaryOp(Add);

//int answer = b(10, 10); // in main thread, sync mode...

IAsyncResult itf = b.BeginInvoke(10, 10, null, null);

Console.WriteLine("Doing more work in Main()!");

// getting result

int answer = b.EndInvoke(itf);

Console.WriteLine("10 + 10 is {0}", answer);

Console.ReadLine();

}

static void ASyncCall2() // << allows work in main thread

{

Console.WriteLine("*** ASync Delegate Review ***");

Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

BinaryOp b = new BinaryOp(Add);

//int answer = b(10, 10); // in main thread, sync mode...

IAsyncResult itf = b.BeginInvoke(10, 10, null, null);

while (!itf.IsCompleted) // always ask additional thread IsCompleted and works during this

{

Console.WriteLine("DoingMoreWorkInMain");

Thread.Sleep(1000);

}

Console.WriteLine("Doing more work in Main()!");

int answer = b.EndInvoke(itf);

Console.WriteLine("10 + 10 is {0}", answer);

Console.ReadLine();

}

static void ASyncCall3() // << allows work in main thread with max time limit

{

Console.WriteLine("*** ASync Delegate Review ***");

Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

BinaryOp b = new BinaryOp(Add);

//int answer = b(10, 10); // in main thread, sync mode...

IAsyncResult itf = b.BeginInvoke(10, 10, null, null);

while (!itf.AsyncWaitHandle.WaitOne(1000,true)) // max time to wait

//always ask additional thread IsCompleted and works during this

{

Console.WriteLine("DoingMoreWorkInMain");

Thread.Sleep(1000);

}

Console.WriteLine("Doing more work in Main()!");

int answer = b.EndInvoke(itf);

Console.WriteLine("10 + 10 is {0}", answer);

Console.ReadLine();

}

static void AsyncCallBackExample()

{

Console.WriteLine("*** ASyncCallBackExample ***");

Console.WriteLine("Main() invoked on thread {0}", Thread.CurrentThread.ManagedThreadId);

BinaryOp b = new BinaryOp(Add);

//int answer = b(10, 10); // in main thread, sync mode...

IAsyncResult itf = b.BeginInvoke(

10, // delegate param

new AsyncCallback(AddComplete), // CallBack method

"Main() string object added to call back method"); // some object for call back method

while (!isDone) //

{

Console.WriteLine("DoingMoreWorkInMain");

Thread.Sleep(1000);

}

Console.ReadLine();

}

static void AddComplete(IAsyncResult itf)

{

Console.WriteLine("AddComplete() invoked on thread {0} ", Thread.CurrentThread.ManagedThreadId);

AsyncResult ar = (AsyncResult)itf;

BinaryOp b = (BinaryOp)ar.AsyncDelegate;

string msg = (string)itf.AsyncState; // could be any object not only string...

Console.WriteLine("10+10 is {0}",b.EndInvoke(itf));

Console.WriteLine("message from Main " + msg);

isDone = true;

}

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