namespace ConsoleApplication4983
{
    public class MyClass
    {
        static void Main()
        {
            var c = new MyClass();
            c.DoSomething(new Sequential());
            c.DoSomething(new Random());
        }

        public void DoSomething(ProcessingMethod method)
        {
            if (method is Sequential)
            {
                // do something sequential
            }
            else if (method is Random)
            {
                // do something random
            }
        }
    }

    public class ProcessingMethod {}
    public class Sequential : ProcessingMethod {}
    public class Random : ProcessingMethod {}
}

using System;

namespace ConsoleApplication4983
{
    public class MyClass
    {
    	static void Main()
    	{
    		var c = new MyClass();
    		c.DoSomething(new Sequential());
    		c.DoSomething(new Random());
    	}

    	public void DoSomething(ProcessingMethod method)
    	{
    		method.Foo();
    	}
    }

    public class ProcessingMethod
    {
    	public virtual void Foo() { }
    }
    public class Sequential : ProcessingMethod
    {
    	public override void Foo() { }
    }
    public class Random : ProcessingMethod
    {
    	public override void Foo() { }
    }
}

public interface IProcessingMethod
{
    void Process();
}

public class SequentialProcess : IProcessingMethod
{
    public void Process( IProcessable obj )
    {
         do something sequentially with the obj
    }
}

public class ParallelProcess : IProcessingMethod
{
    public void Process( IProcessable obj )
    {
        do something in parallel with the obj
    }
}

public interface IProcessable
{
    void Process( IProcessingMethod method );
}

public class MyClass : IProcessable
{
     public void Process( IProcessingMethod method )
     {
         method.Process( this );
     }
}

...

var obj = new MyClass();
obj.Process( new SequentialProcess() );

public void DoSomething(ProcessingMethod method)    {
   method.DoSomething();
}

public void DoSomething(ProcessingMethod method)
{
  method.Process();
}

public abstract class ProcessingMethod
{
  public abstract void Process();
}

public class Sequental : ProcessingMethod
{
  public override void Process()
  {
    // do something sequential
  }
}

public class Random : ProcessingMethod
{
  public override void Process()
  {
    // do something random
  }
}

public class Parallel : ProcessingMethod{}

namespace ConsoleApplication4983
{
    public class MyClass
    {
        static void Main()
        {
            var c = new MyClass();
            c.DoSomething(ProcessingMethod.Sequential);
            c.DoSomething(ProcessingMethod.Random);
        }

        public void DoSomething(ProcessingMethod method)
        {
            if (method == ProcessingMethod.Sequential)
            {
                // do something sequential
            }
            else if (method == ProcessingMethod.Random)
            {
                // do something random
            }
        }
    }

    public enum ProcessingMethod
    {
        Sequential,
        Random
    }
}