TransactionScope.Complete メソッド

定義

スコープ内のすべての操作が正常に完了したことを示します。Indicates that all operations within the scope are completed successfully.

public:
 void Complete();
public void Complete ();
member this.Complete : unit -> unit
Public Sub Complete ()

例外

このメソッドは、既に一度呼び出されています。This method has already been called once.

次の例では、TransactionScope クラスを使用して、トランザクションに参加するコードのブロックを定義する方法を示します。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

注釈

スコープ内のすべての操作が正常に完了したことがわかったら、このメソッドを1回だけ呼び出して、すべてのリソースの状態が一貫していることと、トランザクションをコミットできることをトランザクションマネージャーに通知します。When you are satisfied that all operations within the scope are completed successfully, you should call this method only once to inform that transaction manager that the state across all resources is consistent, and the transaction can be committed. 呼び出しを using ブロックの最後のステートメントとして配置することをお勧めします。It is very good practice to put the call as the last statement in the using block.

このメソッドの使用方法の詳細については、「トランザクションスコープを使用した暗黙のトランザクションの実装」を参照してください。For more information on how this method is used, see the Implementing An Implicit Transaction Using Transaction Scope topic.

このメソッドを呼び出さないと、トランザクションマネージャーはこれをシステム障害として、またはトランザクションのスコープ内でスローされた例外として解釈するので、トランザクションを中止します。Failing to call this method aborts the transaction, because the transaction manager interprets this as a system failure, or exceptions thrown within the scope of transaction. ただし、このメソッドを呼び出すと、トランザクションのコミットは保証されないことにも注意してください。However, you should also note that calling this method does not guarantee a commit of the transaction. これはトランザクション マネージャーにステータスを通知する手段にすぎません。It is merely a way of informing the transaction manager of your status. このメソッドを呼び出した後、Current プロパティを使用してアンビエントトランザクションにアクセスすることはできなくなります。これを試みると、例外がスローされます。After calling this method, you can no longer access the ambient transaction via the Current property, and trying to do so results in an exception being thrown.

TransactionScope オブジェクトでトランザクションが作成された場合、リソースマネージャー間のコミットの実際の処理は、End Using ステートメントで行われます。The actual work of commit between the resources manager happens at the End Using statement if the TransactionScope object created the transaction. このオブジェクトによってトランザクションが作成されていない場合、Commit オブジェクトの所有者によって CommittableTransaction が呼び出されるたびにコミットが発生します。If it did not create the transaction, the commit occurs whenever Commit is called by the owner of the CommittableTransaction object. この時点で、トランザクションマネージャーはリソースマネージャーを呼び出し、TransactionScope オブジェクトでこのメソッドが呼び出されたかどうかに基づいて、コミットまたはロールバックのいずれかに通知します。At that point the Transaction Manager calls the resource managers and informs them to either commit or rollback, based on whether this method was called on the TransactionScope object.

適用対象

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