C# Transaction 事务处理

class

 //student
  [Serializable]
     public class Student
     {
         public string FirstName { get; set; }
         public string LastName { get; set; }
         public string Company { get; set; }
         public int Id { get; set; }

         public override string ToString()
         {
             return String.Format("{0} {1}", FirstName, LastName);
         }
     }

 //student 处理类
  public async Task AddStudentAsync(Student student, Transaction tx)
         {
             SqlConnection connection = new SqlConnection(Settings.Default.CourseConnection);
             await connection.OpenAsync();
             try
             {
                 if (tx != null)
                     connection.EnlistTransaction(tx);
                 SqlCommand command = connection.CreateCommand();
                 command.CommandText = "INSERT INTO Students (FirstName, LastName, Company) " +
                "VALUES (@FirstName, @LastName, @Company)";
                 command.Parameters.AddWithValue("@FirstName", student.FirstName);
                 command.Parameters.AddWithValue("@LastName", student.LastName);
                 command.Parameters.AddWithValue("@Company", student.Company);
                 await command.ExecuteNonQueryAsync();
             }
             catch (Exception ex)
             {
                 Trace.WriteLine("AddStudentAsync(Student student, Transaction tx) Error :" + ex.Message);
                 throw;
             }
             finally
             { connection.Close(); }
         }

 //操作类
   public static class Utilities
     {
        public static bool AbortTx()
        {
            Console.Write("Abort the Transaction (y/n)?");
            return Console.ReadLine().ToLower().Equals("y");
        }
        public static void DisplayTransactionInformation(string title, TransactionInformation ti)
        {
            Contract.Requires<ArgumentNullException>(ti != null);

            Console.WriteLine(title);
            Console.WriteLine("Creation Time: {0:T}", ti.CreationTime);
            Console.WriteLine("Status: {0}", ti.Status);
            Console.WriteLine("Local ID: {0}", ti.LocalIdentifier);
            Console.WriteLine("Distributed ID: {0}", ti.DistributedIdentifier);
            Console.WriteLine();
        }
     }

执行类

   static void Main(string[] args)
         {
            Task t= CommittableTransactionAsync();
            t.Wait();
         }
         static async Task CommittableTransactionAsync()
         {
             var tx = new CommittableTransaction();
             Utilities.DisplayTransactionInformation("TX created", tx.TransactionInformation);

             try
             {
                 var s1 = new Student() { FirstName = "Stephanie", LastName = "Nage1", Company = "China" };
                 var db = new StudentData();
                 await db.AddStudentAsync(s1,tx);

                 var s2 = new Student() { FirstName = "Stephanie2", LastName = "Nage2", Company = "China" };
                 await db.AddStudentAsync(s2, tx);

                 Utilities.DisplayTransactionInformation("2nd connection enlisted ", tx.TransactionInformation);

                 if(Utilities.AbortTx())
                 {
                     throw new ApplicationException("transaction abort");
                 }
                 tx.Commit();
             }
             catch (Exception ex)
             {
                 Console.WriteLine(ex.Message);
                 Console.WriteLine();
                 tx.Rollback();
             }
             Utilities.DisplayTransactionInformation("TX completed", tx.TransactionInformation);
         }