This method enables applications to explicitly enlist in a specific distributed transaction after a connection has been opened.

Declaration

// C#
public void EnlistDistributedTransaction(ITransaction transaction);

Parameters

• transaction

  An ITransaction interface.

Exceptions

InvalidOperationException - The connection is part of a local transaction or the connection is closed.

Remarks

EnlistDistributedTransaction enables objects to enlist in a specific transaction that is passed to the method. The ITransaction interface can be obtained by applying an (ITransaction) cast to the ContexUtil.Transaction property within the component that started the distributed transaction.

The connection must be open before calling this method or an InvalidOperationException is thrown.

If a connection is part of a local transaction that was started implicitly or explicitly while attempting to enlist in a distributed transaction, the local transaction is rolled back and an exception is thrown.

By default, distributed transactions roll back, unless the method-level AutoComplete declaration is set.

Invoking the commit on the ITranasction raises an exception.

Invoking the rollback on the ITransaction method and calling ContextUtil.SetComplete on the same distributed transaction raises an exception.

Remarks (.NET Stored Procedure)

Using this method causes a Not Supported exception.

Example

Application:

// C#
 
/* This is the class that will utilize the Enterprise Services 
   component.  This module needs to be built as an executable.
   
   The Enterprise Services Component DLL must be built first 
   before building this module. 
   In addition, the DLL needs to be referenced appropriately 
   when building this application. 
*/
 
using System;
using System.EnterpriseServices;
using DistribTxnSample;
 
class DistribTxnSample_App
{
  static void Main()
  {
    DistribTxnSample_Comp comp = new DistribTxnSample_Comp();
    comp.DoWork();
  }
}

Component:

// C#
 
/* This module needs to be
   1) built as a component DLL/Library
   2) built with a strong name
   
  This library must be built first before the application is built.
*/ 
 
using System;
using System.Data;
using Oracle.DataAccess.Client; 
using System.EnterpriseServices;
 
namespace DistribTxnSample
{
  [Transaction(TransactionOption.RequiresNew)]
  public class DistribTxnSample_Comp : ServicedComponent
  {
    public void DoWork()
    {   
      string constr = 
        "User Id=scott;Password=tiger;Data Source=oracle;enlist=false";
      OracleConnection con = new OracleConnection(constr);
      con.Open();
 
      // Enlist in a distrubuted transaction
      con.EnlistDistributedTransaction((ITransaction)ContextUtil.Transaction);
 
      // Update EMP table
      OracleCommand cmd = con.CreateCommand();
      cmd.CommandText = "UPDATE emp set sal = sal + .01";
      cmd.ExecuteNonQuery();
 
      // Commit
      ContextUtil.SetComplete();
 
      // Dispose OracleConnection object
      con.Dispose();
    }
  }
}