Chain of Responsibility design pattern example

Approver.cs

namespace ChainOfResponsibility
{
    //Handler class
    public abstract class Approver
    {
        public abstract void HandleRequest(int requestAmount);
        protected Approver NextApprover;
        public void SetNextApprover(Approver approver)
        {
            NextApprover = approver;
        }
    }
}

Director.cs

using System;

namespace ChainOfResponsibility
{
    //Concrete Handler class
    public class Director : Approver
    {
        public override void HandleRequest(int requestAmount)
        {
            if (requestAmount < 300000)
                Console.WriteLine("Director has approved amount - {0}", requestAmount);
            else if (NextApprover != null)
                NextApprover.HandleRequest(requestAmount);
        }
    }
}

Manager.cs

using System;

namespace ChainOfResponsibility
{
    //Concrete Handler class
    public class Manager : Approver
    {
        public override void HandleRequest(int requestAmount)
        {
            if (requestAmount < 100000)
                Console.WriteLine("Manager has approved amount - {0}", requestAmount);
            else if (NextApprover != null)
                NextApprover.HandleRequest(requestAmount);
        }
    }
}

Program.cs

using System;

namespace ChainOfResponsibility
{
    class Program
    {
        //Client Class
        static void Main(string[] args)
        {
            //Create classes of chain of responsibility
            Approver Manager = new Manager();
            Approver SeniorManager = new SeniorManager();
            Approver Director = new Director();

            //Set next request approver or handler
            Manager.SetNextApprover(SeniorManager);
            SeniorManager.SetNextApprover(Director);

            //Create requests.
            Manager.HandleRequest(75000);
            Manager.HandleRequest(150000);
            Manager.HandleRequest(250000);

            Console.ReadLine();
        }
    }
}

SeniorManager.cs

using System;

namespace ChainOfResponsibility
{
    //Concrete Handler class
    public class SeniorManager : Approver
    {
        public override void HandleRequest(int requestAmount)
        {
            if (requestAmount < 200000)
                Console.WriteLine("Senior Manager has approved amount - {0}", requestAmount);
            else if (NextApprover != null)
                NextApprover.HandleRequest(requestAmount);
        }
    }
}

Chain of Responsibility Pattern