• Articolo

Procedura: Creazione di una sottoscrizione pull (programmazione RMO)

È possibile creare sottoscrizioni pull a livello di programmazione tramite gli oggetti RMO (Replication Management Objects). Le classi RMO utilizzate per la creazione di una sottoscrizione pull dipendono dal tipo di pubblicazione a cui appartiene la sottoscrizione.

Per creare una sottoscrizione pull di una pubblicazione snapshot o transazionale

  1. Creare una connessione sia al Sottoscrittore che al server di pubblicazione tramite la classe ServerConnection.

  2. Creare un'istanza della classe TransPublication utilizzando la connessione al server di pubblicazione creata nel passaggio 1. Specificare Name, DatabaseName e ConnectionContext.

  3. Chiamare il metodo LoadProperties. Se il metodo restituisce false, le proprietà specificate nel passaggio 2 non sono corrette oppure la pubblicazione non esiste nel server.

  4. Eseguire un'operazione con AND logico bit per bit (& in Visual C# e And in Visual Basic) tra la proprietà Attributes e AllowPull. Se il risultato è None, impostare Attributes sul risultato di un'operazione con OR logico bit per bit (| in Visual C# e Or in Visual Basic) tra Attributes e AllowPull. Chiamare quindi CommitPropertyChanges per attivare le sottoscrizioni pull.

  5. Se il database di sottoscrizione non esiste, crearlo utilizzando la classe Database. Per ulteriori informazioni, vedere Creazione, modifica e rimozione di database.

  6. Creare un'istanza della classe TransPullSubscription.

  7. Impostare le proprietà seguenti per la sottoscrizione:

  8. Chiamare il metodo Create.

  9. Utilizzando l'istanza della classe TransPublication creata nel passaggio 2, chiamare il metodo MakePullSubscriptionWellKnown per registrare la sottoscrizione pull nel server di pubblicazione. Se la registrazione esiste già, viene generata un'eccezione.

Per creare una sottoscrizione pull di una pubblicazione di tipo merge

  1. Creare una connessione sia al Sottoscrittore che al server di pubblicazione tramite la classe ServerConnection.

  2. Creare un'istanza della classe MergePublication utilizzando la connessione al server di pubblicazione creata nel passaggio 1. Specificare Name, DatabaseName e ConnectionContext.

  3. Chiamare il metodo LoadProperties. Se il metodo restituisce false, le proprietà specificate nel passaggio 2 non sono corrette oppure la pubblicazione non esiste nel server.

  4. Eseguire un'operazione con AND logico bit per bit (& in Visual C# e And in Visual Basic) tra la proprietà Attributes e AllowPull. Se il risultato è None, impostare Attributes sul risultato di un'operazione con OR logico bit per bit (| in Visual C# e Or in Visual Basic) tra Attributes e AllowPull. Chiamare quindi CommitPropertyChanges per attivare le sottoscrizioni pull.

  5. Se il database di sottoscrizione non esiste, crearlo utilizzando la classe Database. Per ulteriori informazioni, vedere Creazione, modifica e rimozione di database.

  6. Creare un'istanza della classe MergePullSubscription.

  7. Impostare le proprietà seguenti per la sottoscrizione:

  8. Chiamare il metodo Create.

  9. Utilizzando l'istanza della classe MergePublication creata nel passaggio 2, chiamare il metodo MakePullSubscriptionWellKnown per registrare la sottoscrizione pull nel server di pubblicazione. Se la registrazione esiste già, viene generata un'eccezione.

Esempio

In questo esempio viene creata una sottoscrizione pull di una pubblicazione transazionale. Le credenziali dell'account di Microsoft Windows utilizzate per creare il processo dell'agente di distribuzione vengono passate in fase di esecuzione.

            // Define the Publisher, publication, and databases.
            string publicationName = "AdvWorksProductTran";
            string publisherName = publisherInstance;
            string subscriberName = subscriberInstance;
            string subscriptionDbName = "AdventureWorks2008R2Replica";
            string publicationDbName = "AdventureWorks2008R2";

            //Create connections to the Publisher and Subscriber.
            ServerConnection subscriberConn = new ServerConnection(subscriberName);
            ServerConnection publisherConn = new ServerConnection(publisherName);

            // Create the objects that we need.
            TransPublication publication;
            TransPullSubscription subscription;

            try
            {
                // Connect to the Publisher and Subscriber.
                subscriberConn.Connect();
                publisherConn.Connect();

                // Ensure that the publication exists and that 
                // it supports pull subscriptions.
                publication = new TransPublication();
                publication.Name = publicationName;
                publication.DatabaseName = publicationDbName;
                publication.ConnectionContext = publisherConn;

                if (publication.IsExistingObject)
                {
                    if ((publication.Attributes & PublicationAttributes.AllowPull) == 0)
                    {
                        publication.Attributes |= PublicationAttributes.AllowPull;
                    }

                    // Define the pull subscription.
                    subscription = new TransPullSubscription();
                    subscription.ConnectionContext = subscriberConn;
                    subscription.PublisherName = publisherName;
                    subscription.PublicationName = publicationName;
                    subscription.PublicationDBName = publicationDbName;
                    subscription.DatabaseName = subscriptionDbName;

                    // Specify the Windows login credentials for the Distribution Agent job.
                    subscription.SynchronizationAgentProcessSecurity.Login = winLogin;
                    subscription.SynchronizationAgentProcessSecurity.Password = winPassword;

                    // Make sure that the agent job for the subscription is created.
                    subscription.CreateSyncAgentByDefault = true;

                    // By default, subscriptions to transactional publications are synchronized 
                    // continuously, but in this case we only want to synchronize on demand.
                    subscription.AgentSchedule.FrequencyType = ScheduleFrequencyType.OnDemand;

                    // Create the pull subscription at the Subscriber.
                    subscription.Create();

                    Boolean registered = false;

                    // Verify that the subscription is not already registered.
                    foreach (TransSubscription existing
                        in publication.EnumSubscriptions())
                    {
                        if (existing.SubscriberName == subscriberName
                            && existing.SubscriptionDBName == subscriptionDbName)
                        {
                            registered = true;
                        }
                    }
                    if (!registered)
                    {
                        // Register the subscription with the Publisher.
                        publication.MakePullSubscriptionWellKnown(
                            subscriberName, subscriptionDbName,
                            SubscriptionSyncType.Automatic,
                            TransSubscriberType.ReadOnly);
                    }
                }
                else
                {
                    // Do something here if the publication does not exist.
                    throw new ApplicationException(String.Format(
                        "The publication '{0}' does not exist on {1}.",
                        publicationName, publisherName));
                }
            }
            catch (Exception ex)
            {
                // Implement the appropriate error handling here.
                throw new ApplicationException(String.Format(
                    "The subscription to {0} could not be created.", publicationName), ex);
            }
            finally
            {
                subscriberConn.Disconnect();
                publisherConn.Disconnect();
            }

' Define the Publisher, publication, and databases.
Dim publicationName As String = "AdvWorksProductTran"
Dim publisherName As String = publisherInstance
Dim subscriberName As String = subscriberInstance
Dim subscriptionDbName As String = "AdventureWorks2008R2Replica"
Dim publicationDbName As String = "AdventureWorks2008R2"

'Create connections to the Publisher and Subscriber.
Dim subscriberConn As ServerConnection = New ServerConnection(subscriberName)
Dim publisherConn As ServerConnection = New ServerConnection(publisherName)

' Create the objects that we need.
Dim publication As TransPublication
Dim subscription As TransPullSubscription

Try
    ' Connect to the Publisher and Subscriber.
    subscriberConn.Connect()
    publisherConn.Connect()

    ' Ensure that the publication exists and that 
    ' it supports pull subscriptions.
    publication = New TransPublication()
    publication.Name = publicationName
    publication.DatabaseName = publicationDbName
    publication.ConnectionContext = publisherConn

    If publication.IsExistingObject Then
        If (publication.Attributes And PublicationAttributes.AllowPull) = 0 Then
            publication.Attributes = publication.Attributes _
            Or PublicationAttributes.AllowPull
        End If

        ' Define the pull subscription.
        subscription = New TransPullSubscription()
        subscription.ConnectionContext = subscriberConn
        subscription.PublisherName = publisherName
        subscription.PublicationName = publicationName
        subscription.PublicationDBName = publicationDbName
        subscription.DatabaseName = subscriptionDbName
        subscription.Description = "Pull subscription to " + publicationDbName _
        + " on " + subscriberName + "."

        ' Specify the Windows login credentials for the Distribution Agent job.
        subscription.SynchronizationAgentProcessSecurity.Login = winLogin
        subscription.SynchronizationAgentProcessSecurity.Password = winPassword

        ' Make sure that the agent job for the subscription is created.
        subscription.CreateSyncAgentByDefault = True

        ' By default, subscriptions to transactional publications are synchronized 
        ' continuously, but in this case we only want to synchronize on demand.
        subscription.AgentSchedule.FrequencyType = ScheduleFrequencyType.OnDemand

        ' Create the pull subscription at the Subscriber.
        subscription.Create()

        Dim registered As Boolean = False

        ' Verify that the subscription is not already registered.
        For Each existing As TransSubscription In publication.EnumSubscriptions()
            If existing.SubscriberName = subscriberName And _
                existing.SubscriptionDBName = subscriptionDbName Then
                registered = True
            End If
        Next existing
        If Not registered Then
            ' Register the subscription with the Publisher.
            publication.MakePullSubscriptionWellKnown( _
             subscriberName, subscriptionDbName, _
             SubscriptionSyncType.Automatic, _
             TransSubscriberType.ReadOnly)
        End If
    Else
        ' Do something here if the publication does not exist.
        Throw New ApplicationException(String.Format( _
         "The publication '{0}' does not exist on {1}.", _
         publicationName, publisherName))
    End If
Catch ex As Exception
    ' Implement the appropriate error handling here.
    Throw New ApplicationException(String.Format( _
        "The subscription to {0} could not be created.", publicationName), ex)
Finally
    subscriberConn.Disconnect()
    publisherConn.Disconnect()
End Try

In questo esempio viene creata una sottoscrizione pull di una pubblicazione di tipo merge. Le credenziali dell'account di Windows utilizzate per creare il processo dell'agente di merge vengono passate in fase di esecuzione.

            // Define the Publisher, publication, and databases.
            string publicationName = "AdvWorksSalesOrdersMerge";
            string publisherName = publisherInstance;
            string subscriberName = subscriberInstance;
            string subscriptionDbName = "AdventureWorks2008R2Replica";
            string publicationDbName = "AdventureWorks2008R2";
            string hostname = @"adventure-works\garrett1";

            //Create connections to the Publisher and Subscriber.
            ServerConnection subscriberConn = new ServerConnection(subscriberName);
            ServerConnection publisherConn = new ServerConnection(publisherName);

            // Create the objects that we need.
            MergePublication publication;
            MergePullSubscription subscription;

            try
            {
                // Connect to the Subscriber.
                subscriberConn.Connect();

                // Ensure that the publication exists and that 
                // it supports pull subscriptions.
                publication = new MergePublication();
                publication.Name = publicationName;
                publication.DatabaseName = publicationDbName;
                publication.ConnectionContext = publisherConn;

                if (publication.LoadProperties())
                {
                    if ((publication.Attributes & PublicationAttributes.AllowPull) == 0)
                    {
                        publication.Attributes |= PublicationAttributes.AllowPull;
                    }

                    // Define the pull subscription.
                    subscription = new MergePullSubscription();
                    subscription.ConnectionContext = subscriberConn;
                    subscription.PublisherName = publisherName;
                    subscription.PublicationName = publicationName;
                    subscription.PublicationDBName = publicationDbName;
                    subscription.DatabaseName = subscriptionDbName;
                    subscription.HostName = hostname;

                    // Specify the Windows login credentials for the Merge Agent job.
                    subscription.SynchronizationAgentProcessSecurity.Login = winLogin;
                    subscription.SynchronizationAgentProcessSecurity.Password = winPassword;

                    // Make sure that the agent job for the subscription is created.
                    subscription.CreateSyncAgentByDefault = true;

                    // Create the pull subscription at the Subscriber.
                    subscription.Create();

                    Boolean registered = false;

                    // Verify that the subscription is not already registered.
                    foreach (MergeSubscription existing
                        in publication.EnumSubscriptions())
                    {
                        if (existing.SubscriberName == subscriberName
                            && existing.SubscriptionDBName == subscriptionDbName
                            && existing.SubscriptionType == SubscriptionOption.Pull)
                        {
                            registered = true;
                        }
                    }
                    if (!registered)
                    {
                        // Register the local subscription with the Publisher.
                        publication.MakePullSubscriptionWellKnown(
                            subscriberName, subscriptionDbName,
                            SubscriptionSyncType.Automatic,
                            MergeSubscriberType.Local, 0);
                    }
                }
                else
                {
                    // Do something here if the publication does not exist.
                    throw new ApplicationException(String.Format(
                        "The publication '{0}' does not exist on {1}.",
                        publicationName, publisherName));
                }
            }
            catch (Exception ex)
            {
                // Implement the appropriate error handling here.
                throw new ApplicationException(String.Format(
                    "The subscription to {0} could not be created.", publicationName), ex);
            }
            finally
            {
                subscriberConn.Disconnect();
                publisherConn.Disconnect();
            }

' Define the Publisher, publication, and databases.
Dim publicationName As String = "AdvWorksSalesOrdersMerge"
Dim publisherName As String = publisherInstance
Dim subscriberName As String = subscriberInstance
Dim subscriptionDbName As String = "AdventureWorks2008R2Replica"
Dim publicationDbName As String = "AdventureWorks2008R2"
Dim hostname As String = "adventure-works\garrett1"

'Create connections to the Publisher and Subscriber.
Dim subscriberConn As ServerConnection = New ServerConnection(subscriberName)
Dim publisherConn As ServerConnection = New ServerConnection(publisherName)

' Create the objects that we need.
Dim publication As MergePublication
Dim subscription As MergePullSubscription

Try
    ' Connect to the Subscriber.
    subscriberConn.Connect()

    ' Ensure that the publication exists and that 
    ' it supports pull subscriptions.
    publication = New MergePublication()
    publication.Name = publicationName
    publication.DatabaseName = publicationDbName
    publication.ConnectionContext = publisherConn

    If publication.LoadProperties() Then
        If (publication.Attributes And PublicationAttributes.AllowPull) = 0 Then
            publication.Attributes = publication.Attributes _
            Or PublicationAttributes.AllowPull
        End If

        ' Define the pull subscription.
        subscription = New MergePullSubscription()
        subscription.ConnectionContext = subscriberConn
        subscription.PublisherName = publisherName
        subscription.PublicationName = publicationName
        subscription.PublicationDBName = publicationDbName
        subscription.DatabaseName = subscriptionDbName
        subscription.HostName = hostname

        ' Specify the Windows login credentials for the Merge Agent job.
        subscription.SynchronizationAgentProcessSecurity.Login = winLogin
        subscription.SynchronizationAgentProcessSecurity.Password = winPassword

        ' Make sure that the agent job for the subscription is created.
        subscription.CreateSyncAgentByDefault = True

        ' Create the pull subscription at the Subscriber.
        subscription.Create()

        Dim registered As Boolean = False

        ' Verify that the subscription is not already registered.
        For Each existing As MergeSubscription In _
        publication.EnumSubscriptions()
            If existing.SubscriberName = subscriberName Then
                registered = True
            End If
        Next
        If Not registered Then
            ' Register the local subscription with the Publisher.
            publication.MakePullSubscriptionWellKnown( _
             subscriberName, subscriptionDbName, _
             SubscriptionSyncType.Automatic, _
             MergeSubscriberType.Local, 0)
        End If
    Else
        ' Do something here if the publication does not exist.
        Throw New ApplicationException(String.Format( _
         "The publication '{0}' does not exist on {1}.", _
         publicationName, publisherName))
    End If
Catch ex As Exception
    ' Implement the appropriate error handling here.
    Throw New ApplicationException(String.Format( _
        "The subscription to {0} could not be created.", publicationName), ex)
Finally
    subscriberConn.Disconnect()
    publisherConn.Disconnect()
End Try

In questo esempio viene creata una sottoscrizione pull di una pubblicazione di tipo merge senza creare un processo dell'agente associato e i metadati di sottoscrizione in MSsubscription_properties. Le credenziali dell'account di Windows utilizzate per creare il processo dell'agente di merge vengono passate in fase di esecuzione.

         // Define the Publisher, publication, and databases.
            string publicationName = "AdvWorksSalesOrdersMerge";
            string publisherName = publisherInstance;
            string subscriberName = subscriberInstance;
            string subscriptionDbName = "AdventureWorks2008R2Replica";
            string publicationDbName = "AdventureWorks2008R2";

            //Create connections to the Publisher and Subscriber.
            ServerConnection subscriberConn = new ServerConnection(subscriberName);
            ServerConnection publisherConn = new ServerConnection(publisherName);

            // Create the objects that we need.
            MergePublication publication;
            MergePullSubscription subscription;

            try
            {
                // Connect to the Subscriber.
                subscriberConn.Connect();

                // Ensure that the publication exists and that 
                // it supports pull subscriptions.
                publication = new MergePublication();
                publication.Name = publicationName;
                publication.DatabaseName = publicationDbName;
                publication.ConnectionContext = publisherConn;

                if (publication.LoadProperties())
                {
                    if ((publication.Attributes & PublicationAttributes.AllowPull) == 0)
                    {
                        publication.Attributes |= PublicationAttributes.AllowPull;
                    }

                    // Define the pull subscription.
                    subscription = new MergePullSubscription();
                    subscription.ConnectionContext = subscriberConn;
                    subscription.PublisherName = publisherName;
                    subscription.PublicationName = publicationName;
                    subscription.PublicationDBName = publicationDbName;
                    subscription.DatabaseName = subscriptionDbName;

                    // Specify that an agent job not be created for this subscription. The
                    // subscription can only be synchronized by running the Merge Agent directly.
                    // Subscripition metadata stored in MSsubscription_properties will not
                    // be available and must be specified at run time.
                    subscription.CreateSyncAgentByDefault = false;

                    // Create the pull subscription at the Subscriber.
                    subscription.Create();

                    Boolean registered = false;

                    // Verify that the subscription is not already registered.
                    foreach (MergeSubscription existing
                        in publication.EnumSubscriptions())
                    {
                        if (existing.SubscriberName == subscriberName
                            && existing.SubscriptionDBName == subscriptionDbName
                            && existing.SubscriptionType == SubscriptionOption.Pull)
                        {
                            registered = true;
                        }
                    }
                    if (!registered)
                    {
                        // Register the local subscription with the Publisher.
                        publication.MakePullSubscriptionWellKnown(
                            subscriberName, subscriptionDbName,
                            SubscriptionSyncType.Automatic,
                            MergeSubscriberType.Local, 0);
                    }
                }
                else
                {
                    // Do something here if the publication does not exist.
                    throw new ApplicationException(String.Format(
                        "The publication '{0}' does not exist on {1}.",
                        publicationName, publisherName));
                }
            }
            catch (Exception ex)
            {
                // Implement the appropriate error handling here.
                throw new ApplicationException(String.Format(
                    "The subscription to {0} could not be created.", publicationName), ex);
            }
            finally
            {
                subscriberConn.Disconnect();
                publisherConn.Disconnect();
            }

' Define the Publisher, publication, and databases.
Dim publicationName As String = "AdvWorksSalesOrdersMerge"
Dim publisherName As String = publisherInstance
Dim subscriberName As String = subscriberInstance
Dim subscriptionDbName As String = "AdventureWorks2008R2Replica"
Dim publicationDbName As String = "AdventureWorks2008R2"

'Create connections to the Publisher and Subscriber.
Dim subscriberConn As ServerConnection = New ServerConnection(subscriberName)
Dim publisherConn As ServerConnection = New ServerConnection(publisherName)

' Create the objects that we need.
Dim publication As MergePublication
Dim subscription As MergePullSubscription

Try
    ' Connect to the Subscriber.
    subscriberConn.Connect()

    ' Ensure that the publication exists and that 
    ' it supports pull subscriptions.
    publication = New MergePublication()
    publication.Name = publicationName
    publication.DatabaseName = publicationDbName
    publication.ConnectionContext = publisherConn

    If publication.LoadProperties() Then
        If (publication.Attributes And PublicationAttributes.AllowPull) = 0 Then
            publication.Attributes = publication.Attributes _
            Or PublicationAttributes.AllowPull
        End If

        ' Define the pull subscription.
        subscription = New MergePullSubscription()
        subscription.ConnectionContext = subscriberConn
        subscription.PublisherName = publisherName
        subscription.PublicationName = publicationName
        subscription.PublicationDBName = publicationDbName
        subscription.DatabaseName = subscriptionDbName

        ' Specify that an agent job not be created for this subscription. The
        ' subscription can only be synchronized by running the Merge Agent directly.
        ' Subscripition metadata stored in MSsubscription_properties will not
        ' be available and must be specified at run time.
        subscription.CreateSyncAgentByDefault = False

        ' Create the pull subscription at the Subscriber.
        subscription.Create()

        Dim registered As Boolean = False

        ' Verify that the subscription is not already registered.
        For Each existing As MergeSubscription In _
        publication.EnumSubscriptions()
            If existing.SubscriberName = subscriberName Then
                registered = True
            End If
        Next
        If Not registered Then
            ' Register the local subscription with the Publisher.
            publication.MakePullSubscriptionWellKnown( _
             subscriberName, subscriptionDbName, _
             SubscriptionSyncType.Automatic, _
             MergeSubscriberType.Local, 0)
        End If
    Else
        ' Do something here if the publication does not exist.
        Throw New ApplicationException(String.Format( _
         "The publication '{0}' does not exist on {1}.", _
         publicationName, publisherName))
    End If
Catch ex As Exception
    ' Implement the appropriate error handling here.
    Throw New ApplicationException(String.Format( _
     "The subscription to {0} could not be created.", publicationName), ex)
Finally
    subscriberConn.Disconnect()
    publisherConn.Disconnect()
End Try

In questo esempio viene creata una sottoscrizione pull di una pubblicazione di tipo merge che può essere sincronizzata su Internet con la sincronizzazione tramite il Web. Le credenziali dell'account di Windows utilizzate per creare il processo dell'agente di merge vengono passate in fase di esecuzione. Per ulteriori informazioni, vedere Procedura: Configurazione della sincronizzazione tramite il Web per la replica di tipo merge (programmazione RMO).

          // Define the Publisher, publication, and databases.
            string publicationName = "AdvWorksSalesOrdersMerge";
            string publisherName = publisherInstance;
            string subscriberName = subscriberInstance;
            string subscriptionDbName = "AdventureWorks2008R2Replica";
            string publicationDbName = "AdventureWorks2008R2";
            string hostname = @"adventure-works\garrett1";
            string webSyncUrl = "https://" + publisherInstance + "/WebSync/replisapi.dll";

            //Create connections to the Publisher and Subscriber.
            ServerConnection subscriberConn = new ServerConnection(subscriberName);
            ServerConnection publisherConn = new ServerConnection(publisherName);

            // Create the objects that we need.
            MergePublication publication;
            MergePullSubscription subscription;

            try
            {
                // Connect to the Subscriber.
                subscriberConn.Connect();

                // Ensure that the publication exists and that 
                // it supports pull subscriptions and Web synchronization.
                publication = new MergePublication();
                publication.Name = publicationName;
                publication.DatabaseName = publicationDbName;
                publication.ConnectionContext = publisherConn;

                if (publication.LoadProperties())
                {
                    if ((publication.Attributes & PublicationAttributes.AllowPull) == 0)
                    {
                        publication.Attributes |= PublicationAttributes.AllowPull;
                    }
                    if ((publication.Attributes & PublicationAttributes.AllowWebSynchronization) == 0)
                    {
                        publication.Attributes |= PublicationAttributes.AllowWebSynchronization;
                    }

                    // Define the pull subscription.
                    subscription = new MergePullSubscription();
                    subscription.ConnectionContext = subscriberConn;
                    subscription.PublisherName = publisherName;
                    subscription.PublicationName = publicationName;
                    subscription.PublicationDBName = publicationDbName;
                    subscription.DatabaseName = subscriptionDbName;
                    subscription.HostName = hostname;

                    // Specify the Windows login credentials for the Merge Agent job.
                    subscription.SynchronizationAgentProcessSecurity.Login = winLogin;
                    subscription.SynchronizationAgentProcessSecurity.Password = winPassword;

                    // Enable Web synchronization.
                    subscription.UseWebSynchronization = true;
                    subscription.InternetUrl = webSyncUrl;

                    // Specify the same Windows credentials to use when connecting to the
                    // Web server using HTTPS Basic Authentication.
                    subscription.InternetSecurityMode = AuthenticationMethod.BasicAuthentication;
                    subscription.InternetLogin = winLogin;
                    subscription.InternetPassword = winPassword;

                    // Ensure that we create a job for this subscription.
                    subscription.CreateSyncAgentByDefault = true;

                    // Create the pull subscription at the Subscriber.
                    subscription.Create();

                    Boolean registered = false;

                    // Verify that the subscription is not already registered.
                    foreach (MergeSubscription existing
                        in publication.EnumSubscriptions())
                    {
                        if (existing.SubscriberName == subscriberName
                            && existing.SubscriptionDBName == subscriptionDbName
                            && existing.SubscriptionType == SubscriptionOption.Pull)
                        {
                            registered = true;
                        }
                    }
                    if (!registered)
                    {
                        // Register the local subscription with the Publisher.
                        publication.MakePullSubscriptionWellKnown(
                            subscriberName, subscriptionDbName,
                            SubscriptionSyncType.Automatic,
                            MergeSubscriberType.Local, 0);
                    }
                }
                else
                {
                    // Do something here if the publication does not exist.
                    throw new ApplicationException(String.Format(
                        "The publication '{0}' does not exist on {1}.",
                        publicationName, publisherName));
                }
            }
            catch (Exception ex)
            {
                // Implement the appropriate error handling here.
                throw new ApplicationException(String.Format(
                    "The subscription to {0} could not be created.", publicationName), ex);
            }
            finally
            {
                subscriberConn.Disconnect();
                publisherConn.Disconnect();
            }

' Define the Publisher, publication, and databases.
Dim publicationName As String = "AdvWorksSalesOrdersMerge"
Dim publisherName As String = publisherInstance
Dim subscriberName As String = subscriberInstance
Dim subscriptionDbName As String = "AdventureWorks2008R2Replica"
Dim publicationDbName As String = "AdventureWorks2008R2"
Dim hostname As String = "adventure-works\garrett1"
Dim webSyncUrl As String = "https://" + publisherInstance + "/WebSync/replisapi.dll"

'Create connections to the Publisher and Subscriber.
Dim subscriberConn As ServerConnection = New ServerConnection(subscriberName)
Dim publisherConn As ServerConnection = New ServerConnection(publisherName)

' Create the objects that we need.
Dim publication As MergePublication
Dim subscription As MergePullSubscription

Try
    ' Connect to the Subscriber.
    subscriberConn.Connect()

    ' Ensure that the publication exists and that 
    ' it supports pull subscriptions and Web synchronization.
    publication = New MergePublication()
    publication.Name = publicationName
    publication.DatabaseName = publicationDbName
    publication.ConnectionContext = publisherConn

    If publication.LoadProperties() Then
        If (publication.Attributes And PublicationAttributes.AllowPull) = 0 Then
            publication.Attributes = publication.Attributes _
            Or PublicationAttributes.AllowPull
        End If
        If (publication.Attributes And PublicationAttributes.AllowWebSynchronization) = 0 Then
            publication.Attributes = publication.Attributes _
            Or PublicationAttributes.AllowWebSynchronization
        End If

        ' Define the pull subscription.
        subscription = New MergePullSubscription()
        subscription.ConnectionContext = subscriberConn
        subscription.PublisherName = publisherName
        subscription.PublicationName = publicationName
        subscription.PublicationDBName = publicationDbName
        subscription.DatabaseName = subscriptionDbName
        subscription.HostName = hostname
        subscription.CreateSyncAgentByDefault = True

        ' Specify the Windows login credentials for the Merge Agent job.
        subscription.SynchronizationAgentProcessSecurity.Login = winLogin
        subscription.SynchronizationAgentProcessSecurity.Password = winPassword

        ' Enable Web synchronization.
        subscription.UseWebSynchronization = True
        subscription.InternetUrl = webSyncUrl

        ' Specify the same Windows credentials to use when connecting to the
        ' Web server using HTTPS Basic Authentication.
        subscription.InternetSecurityMode = AuthenticationMethod.BasicAuthentication
        subscription.InternetLogin = winLogin
        subscription.InternetPassword = winPassword

        ' Create the pull subscription at the Subscriber.
        subscription.Create()

        Dim registered As Boolean = False

        ' Verify that the subscription is not already registered.
        For Each existing As MergeSubscription In _
        publication.EnumSubscriptions()
            If existing.SubscriberName = subscriberName Then
                registered = True
            End If
        Next
        If Not registered Then
            ' Register the local subscription with the Publisher.
            publication.MakePullSubscriptionWellKnown( _
             subscriberName, subscriptionDbName, _
             SubscriptionSyncType.Automatic, _
             MergeSubscriberType.Local, 0)
        End If
    Else
        ' Do something here if the publication does not exist.
        Throw New ApplicationException(String.Format( _
         "The publication '{0}' does not exist on {1}.", _
         publicationName, publisherName))
    End If
Catch ex As Exception
    ' Implement the appropriate error handling here.
    Throw New ApplicationException(String.Format( _
     "The subscription to {0} could not be created.", publicationName), ex)
Finally
    subscriberConn.Disconnect()
    publisherConn.Disconnect()
End Try