TransactionScope TransactionScope TransactionScope TransactionScope Class

Definizione

Rende transazionale un blocco di codice.Makes a code block transactional. Questa classe non può essere ereditata.This class cannot be inherited.

public ref class TransactionScope sealed : IDisposable
public sealed class TransactionScope : IDisposable
type TransactionScope = class
    interface IDisposable
Public NotInheritable Class TransactionScope
Implements IDisposable
Ereditarietà
TransactionScopeTransactionScopeTransactionScopeTransactionScope
Implementazioni

Esempi

Nell'esempio seguente viene illustrato come utilizzare la TransactionScope classe per definire un blocco di codice per partecipare a una transazione.The following example demonstrates how to use the TransactionScope class to define a block of code to participate in a transaction.

// This function takes arguments for 2 connection strings and commands to create a transaction 
// involving two SQL Servers. It returns a value > 0 if the transaction is committed, 0 if the 
// transaction is rolled back. To test this code, you can connect to two different databases 
// on the same server by altering the connection string, or to another 3rd party RDBMS by 
// altering the code in the connection2 code block.
static public int CreateTransactionScope(
    string connectString1, string connectString2,
    string commandText1, string commandText2)
{
    // Initialize the return value to zero and create a StringWriter to display results.
    int returnValue = 0;
    System.IO.StringWriter writer = new System.IO.StringWriter();

    try
    {
        // Create the TransactionScope to execute the commands, guaranteeing
        // that both commands can commit or roll back as a single unit of work.
        using (TransactionScope scope = new TransactionScope())
        {
            using (SqlConnection connection1 = new SqlConnection(connectString1))
            {
                // Opening the connection automatically enlists it in the 
                // TransactionScope as a lightweight transaction.
                connection1.Open();

                // Create the SqlCommand object and execute the first command.
                SqlCommand command1 = new SqlCommand(commandText1, connection1);
                returnValue = command1.ExecuteNonQuery();
                writer.WriteLine("Rows to be affected by command1: {0}", returnValue);

                // If you get here, this means that command1 succeeded. By nesting
                // the using block for connection2 inside that of connection1, you
                // conserve server and network resources as connection2 is opened
                // only when there is a chance that the transaction can commit.   
                using (SqlConnection connection2 = new SqlConnection(connectString2))
                {
                    // The transaction is escalated to a full distributed
                    // transaction when connection2 is opened.
                    connection2.Open();

                    // Execute the second command in the second database.
                    returnValue = 0;
                    SqlCommand command2 = new SqlCommand(commandText2, connection2);
                    returnValue = command2.ExecuteNonQuery();
                    writer.WriteLine("Rows to be affected by command2: {0}", returnValue);
                }
            }

            // The Complete method commits the transaction. If an exception has been thrown,
            // Complete is not  called and the transaction is rolled back.
            scope.Complete();

        }
       
    }
    catch (TransactionAbortedException ex)
    {
        writer.WriteLine("TransactionAbortedException Message: {0}", ex.Message);
    }

    // Display messages.
    Console.WriteLine(writer.ToString());

    return returnValue;
}
'  This function takes arguments for 2 connection strings and commands to create a transaction 
'  involving two SQL Servers. It returns a value > 0 if the transaction is committed, 0 if the 
'  transaction is rolled back. To test this code, you can connect to two different databases 
'  on the same server by altering the connection string, or to another 3rd party RDBMS  
'  by altering the code in the connection2 code block.
Public Function CreateTransactionScope( _
  ByVal connectString1 As String, ByVal connectString2 As String, _
  ByVal commandText1 As String, ByVal commandText2 As String) As Integer

    ' Initialize the return value to zero and create a StringWriter to display results.
    Dim returnValue As Integer = 0
    Dim writer As System.IO.StringWriter = New System.IO.StringWriter

    Try
    ' Create the TransactionScope to execute the commands, guaranteeing
    '  that both commands can commit or roll back as a single unit of work.
        Using scope As New TransactionScope()
            Using connection1 As New SqlConnection(connectString1)
                ' Opening the connection automatically enlists it in the 
                ' TransactionScope as a lightweight transaction.
                connection1.Open()

                ' Create the SqlCommand object and execute the first command.
                Dim command1 As SqlCommand = New SqlCommand(commandText1, connection1)
                returnValue = command1.ExecuteNonQuery()
                writer.WriteLine("Rows to be affected by command1: {0}", returnValue)

                ' If you get here, this means that command1 succeeded. By nesting
                ' the using block for connection2 inside that of connection1, you
                ' conserve server and network resources as connection2 is opened
                ' only when there is a chance that the transaction can commit.   
                Using connection2 As New SqlConnection(connectString2)
                    ' The transaction is escalated to a full distributed
                    ' transaction when connection2 is opened.
                    connection2.Open()

                    ' Execute the second command in the second database.
                    returnValue = 0
                    Dim command2 As SqlCommand = New SqlCommand(commandText2, connection2)
                    returnValue = command2.ExecuteNonQuery()
                    writer.WriteLine("Rows to be affected by command2: {0}", returnValue)
                End Using
            End Using

        ' The Complete method commits the transaction. If an exception has been thrown,
        ' Complete is called and the transaction is rolled back.
        scope.Complete()
        End Using
    Catch ex As TransactionAbortedException
        writer.WriteLine("TransactionAbortedException Message: {0}", ex.Message)
    End Try

    ' Display messages.
    Console.WriteLine(writer.ToString())

    Return returnValue
End Function

Commenti

L' System.Transactions infrastruttura fornisce un modello di programmazione esplicito basato Transaction sulla classe, oltre a un modello di programmazione implicito che TransactionScope utilizza la classe, in cui le transazioni vengono gestite automaticamente dall'infrastruttura.The System.Transactions infrastructure provides both an explicit programming model based on the Transaction class, as well as an implicit programming model using the TransactionScope class, in which transactions are automatically managed by the infrastructure.

Importante

Si consiglia di creare transazioni implicite usando la TransactionScope classe, in modo che il contesto della transazione di ambiente venga gestito automaticamente.We recommend that you create implicit transactions using the TransactionScope class, so that the ambient transaction context is automatically managed for you. È inoltre consigliabile utilizzare la TransactionScope classe DependentTransaction e per le applicazioni che richiedono l'utilizzo della stessa transazione tra più chiamate di funzione o più chiamate di thread.You should also use the TransactionScope and DependentTransaction class for applications that require the use of the same transaction across multiple function calls or multiple thread calls. Per ulteriori informazioni su questo modello, vedere l'argomento implementazione di una transazione implicita mediante ambito di transazione .For more information on this model, see the Implementing An Implicit Transaction Using Transaction Scope topic. Per ulteriori informazioni sulla scrittura di un'applicazione transazionale, vedere scrittura di un'applicazione transazionale.For more information on writing a transactional application, see Writing A Transactional Application.

Quando si crea un' TransactionScope istanza di new tramite l'istruzione, la gestione transazioni determina la transazione a cui partecipare.Upon instantiating a TransactionScope by the new statement, the transaction manager determines which transaction to participate in. Una volta deciso, l'ambito partecipa sempre a quella transazione.Once determined, the scope always participates in that transaction. La decisione si basa su due fattori: la presenza di una transazione di ambiente e il valore del parametro TransactionScopeOption del costruttore.The decision is based on two factors: whether an ambient transaction is present and the value of the TransactionScopeOption parameter in the constructor. La transazione di ambiente è la transazione in cui viene eseguito il codice.The ambient transaction is the transaction your code executes in. Per ottenere un riferimento a questa transazione è possibile chiamare la proprietà Transaction.Current statica della classe Transaction.You can obtain a reference to the ambient transaction by calling the static Transaction.Current property of the Transaction class. Per ulteriori informazioni sull'utilizzo di questo parametro, vedere la sezione relativa alla gestione del flusso delle transazioni nell'argomento implementazione di una transazione implicita mediante ambito di transazione .For more information on how this parameter is used, see the "Transaction Flow Management" section of the Implementing An Implicit Transaction Using Transaction Scope topic.

Se non si verifica alcuna eccezione all'interno dell'ambito della transazione, ovvero tra l'inizializzazione dell' TransactionScope oggetto e la chiamata del relativo Dispose metodo, la transazione a cui partecipa l'ambito potrà continuare.If no exception occurs within the transaction scope (that is, between the initialization of the TransactionScope object and the calling of its Dispose method), then the transaction in which the scope participates is allowed to proceed. Se si verifica un'eccezione all'interno dell'ambito della transazione, viene eseguito il rollback della transazione di cui fa parte.If an exception does occur within the transaction scope, the transaction in which it participates will be rolled back.

Quando l'applicazione completa tutto il lavoro che si desidera eseguire in una transazione, è consigliabile chiamare il Complete metodo solo una volta per indicare al gestore delle transazioni che è accettabile eseguire il commit della transazione.When your application completes all work it wants to perform in a transaction, you should call the Complete method only once to inform that transaction manager that it is acceptable to commit the transaction. La mancata chiamata di questo metodo interrompe la transazione.Failing to call this method aborts the transaction.

Una chiamata al Dispose metodo contrassegna la fine dell'ambito della transazione.A call to the Dispose method marks the end of the transaction scope. Le eccezioni che si verificano dopo la chiamata a questo metodo potrebbero non avere alcun effetto sulla transazione.Exceptions that occur after calling this method may not affect the transaction.

Se si modifica il valore di Current all'interno di un ambito, viene generata un' Dispose eccezione quando viene chiamato il metodo.If you modify the value of Current inside a scope, an exception is thrown when Dispose is called. Tuttavia, alla fine dell'ambito, viene ripristinato il valore precedente.However, at the end of the scope, the previous value is restored. Inoltre, se si chiama Dispose on Current all'interno di un ambito di transazione che ha creato la transazione, la transazione viene interrotta alla fine dell'ambito.In addition, if you call Dispose on Current inside a transaction scope that created the transaction, the transaction aborts at the end of the scope.

Costruttori

TransactionScope() TransactionScope() TransactionScope() TransactionScope()

Inizializza una nuova istanza della classe TransactionScope.Initializes a new instance of the TransactionScope class.

TransactionScope(Transaction) TransactionScope(Transaction) TransactionScope(Transaction) TransactionScope(Transaction)

Inizializza una nuova istanza della classe TransactionScope e imposta la transazione specificata come transazione di ambiente, in modo che venga utilizzata dalle operazioni transazionali effettuate all'interno dell'ambito.Initializes a new instance of the TransactionScope class and sets the specified transaction as the ambient transaction, so that transactional work done inside the scope uses this transaction.

TransactionScope(Transaction, TimeSpan) TransactionScope(Transaction, TimeSpan) TransactionScope(Transaction, TimeSpan) TransactionScope(Transaction, TimeSpan)

Inizializza una nuova istanza della classe TransactionScope con il valore di timeout specificato e imposta la transazione specificata come transazione di ambiente, in modo che venga utilizzata dalle operazioni transazionali effettuate all'interno dell'ambito.Initializes a new instance of the TransactionScope class with the specified timeout value, and sets the specified transaction as the ambient transaction, so that transactional work done inside the scope uses this transaction.

TransactionScope(Transaction, TimeSpan, EnterpriseServicesInteropOption) TransactionScope(Transaction, TimeSpan, EnterpriseServicesInteropOption) TransactionScope(Transaction, TimeSpan, EnterpriseServicesInteropOption) TransactionScope(Transaction, TimeSpan, EnterpriseServicesInteropOption)

Inizializza una nuova istanza della classe TransactionScope con il valore di timeout e i requisiti di interoperabilità COM+ specificati e imposta la transazione specificata come transazione di ambiente, in modo che venga utilizzata dalle operazioni transazionali effettuate all'interno dell'ambito.Initializes a new instance of the TransactionScope class with the specified timeout value and COM+ interoperability requirements, and sets the specified transaction as the ambient transaction, so that transactional work done inside the scope uses this transaction.

TransactionScope(Transaction, TimeSpan, TransactionScopeAsyncFlowOption) TransactionScope(Transaction, TimeSpan, TransactionScopeAsyncFlowOption) TransactionScope(Transaction, TimeSpan, TransactionScopeAsyncFlowOption) TransactionScope(Transaction, TimeSpan, TransactionScopeAsyncFlowOption)

[Supportato in .NET Framework 4.5.1 e versioni successive][Supported in the .NET Framework 4.5.1 and later versions] Inizializza una nuova istanza della classe TransactionScope con il valore di timeout specificato e imposta la transazione specificata come transazione di ambiente, in modo che venga utilizzata dalle operazioni transazionali effettuate all'interno dell'ambito.Initializes a new instance of the TransactionScope class with the specified timeout value, and sets the specified transaction as the ambient transaction, so that transactional work done inside the scope uses this transaction.

TransactionScope(Transaction, TransactionScopeAsyncFlowOption) TransactionScope(Transaction, TransactionScopeAsyncFlowOption) TransactionScope(Transaction, TransactionScopeAsyncFlowOption) TransactionScope(Transaction, TransactionScopeAsyncFlowOption)

[Supportato in .NET Framework 4.5.1 e versioni successive][Supported in the .NET Framework 4.5.1 and later versions] Inizializza una nuova istanza della classe TransactionScope e imposta la transazione specificata come transazione di ambiente, in modo che venga utilizzata dalle operazioni transazionali effettuate all'interno dell'ambito.Initializes a new instance of the TransactionScope class and sets the specified transaction as the ambient transaction, so that transactional work done inside the scope uses this transaction.

TransactionScope(TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeAsyncFlowOption)

Inizializza una nuova istanza della classe TransactionScope con l'opzione del flusso asincrono specificato.Initializes a new instance of the TransactionScope class with the specified asynchronous flow option.

TransactionScope(TransactionScopeOption) TransactionScope(TransactionScopeOption) TransactionScope(TransactionScopeOption) TransactionScope(TransactionScopeOption)

Inizializza una nuova istanza della classe TransactionScope con i requisiti specificati.Initializes a new instance of the TransactionScope class with the specified requirements.

TransactionScope(TransactionScopeOption, TimeSpan) TransactionScope(TransactionScopeOption, TimeSpan) TransactionScope(TransactionScopeOption, TimeSpan) TransactionScope(TransactionScopeOption, TimeSpan)

Inizializza una nuova istanza della classe TransactionScope con il valore di timeout e i requisiti specificati.Initializes a new instance of the TransactionScope class with the specified timeout value and requirements.

TransactionScope(TransactionScopeOption, TimeSpan, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TimeSpan, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TimeSpan, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TimeSpan, TransactionScopeAsyncFlowOption)

Inizializza una nuova istanza della classe TransactionScope con il valore di timeout, i requisiti e le opzioni del flusso asincrono specificati.Initializes a new instance of the TransactionScope class with the specified timeout value, requirements, and asynchronous flow option.

TransactionScope(TransactionScopeOption, TransactionOptions) TransactionScope(TransactionScopeOption, TransactionOptions) TransactionScope(TransactionScopeOption, TransactionOptions) TransactionScope(TransactionScopeOption, TransactionOptions)

Inizializza una nuova istanza della classe TransactionScope con i requisiti specificati.Initializes a new instance of the TransactionScope class with the specified requirements.

TransactionScope(TransactionScopeOption, TransactionOptions, EnterpriseServicesInteropOption) TransactionScope(TransactionScopeOption, TransactionOptions, EnterpriseServicesInteropOption) TransactionScope(TransactionScopeOption, TransactionOptions, EnterpriseServicesInteropOption) TransactionScope(TransactionScopeOption, TransactionOptions, EnterpriseServicesInteropOption)

Inizializza una nuova istanza della classe TransactionScope con l'ambito e i requisiti di interoperabilità COM+ specificati e le opzioni di transazione.Initializes a new instance of the TransactionScope class with the specified scope and COM+ interoperability requirements, and transaction options.

TransactionScope(TransactionScopeOption, TransactionOptions, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TransactionOptions, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TransactionOptions, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TransactionOptions, TransactionScopeAsyncFlowOption)

[Supportato in .NET Framework 4.5.1 e versioni successive][Supported in the .NET Framework 4.5.1 and later versions] Inizializza una nuova istanza della classe TransactionScope con i requisiti e le opzioni del flusso asincrono specificati.Initializes a new instance of the TransactionScope class with the specified requirements and asynchronous flow option.

TransactionScope(TransactionScopeOption, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TransactionScopeAsyncFlowOption) TransactionScope(TransactionScopeOption, TransactionScopeAsyncFlowOption)

Inizializza una nuova istanza della classe TransactionScope con i requisiti e le opzioni del flusso asincrono specificati.Initializes a new instance of the TransactionScope class with the specified requirements and asynchronous flow option.

Metodi

Complete() Complete() Complete() Complete()

Indica che sono state completate tutte le operazioni all'interno dell'ambito.Indicates that all operations within the scope are completed successfully.

Dispose() Dispose() Dispose() Dispose()

Termina l'ambito della transazione.Ends the transaction scope.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Determina se l'oggetto specificato è uguale all'oggetto corrente.Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Funge da funzione hash predefinita.Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

Ottiene l'oggetto Type dell'istanza corrente.Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Crea una copia superficiale dell'oggetto Object corrente.Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

Restituisce una stringa che rappresenta l'oggetto corrente.Returns a string that represents the current object.

(Inherited from Object)

Si applica a

Thread safety

Questo tipo è thread-safe.This type is thread safe.

Vedi anche