trnsample.cs

using System;
using System.Transactions;

namespace TransactionInterceptorSample
{
    class MainClass
    {
        public static void Main(string[] args)
        {

            DoItOne(0);

            using (var trn = new TransactionScope())
            {
                Transaction.Current.TransactionCompleted += (o, e) =>
                {
                    Console.WriteLine("transaction complated");
                };

                DoItOne(0);
                DoItOne(1);

                trn.Complete();
            }

            DoItOne(0);

            Console.ReadKey();
        }

        static void DoItOne(int i)
        {
            if (Transaction.Current != null)
            {    
                if (i == 1)
                    Transaction.Current.Rollback();
                
                Console.WriteLine("transaction is detected:" + Transaction.Current.TransactionInformation.Status);
            }
            else
            {
                Console.WriteLine("there is no transaction in this scope");
            }
        }
    }
}

output:

there is no transaction in this scope
transaction is detected:Active
transaction complated
transaction is detected:Aborted
transaction complated
there is no transaction in this scope