OdbcTransaction.Rollback 方法

定义

命名空间:

System.Data.Odbc

程序集:

System.Data.Odbc.dll

包:

System.Data.Odbc v9.0.0-rc.2.24473.5

从挂起状态回滚事务。

public:
 override void Rollback();

public override void Rollback ();

override this.Rollback : unit -> unit

Public Overrides Sub Rollback ()

例外

Exception

在尝试提交事务时出错。

InvalidOperationException

已提交或回滚事务。

或

连接已断开。

示例

以下示例创建 OdbcConnection 和 OdbcTransaction。 它还演示如何使用 BeginTransaction、 Commit和 Rollback 方法。

public static void ExecuteTransaction(string connectionString)
{
    using (OdbcConnection connection =
               new OdbcConnection(connectionString))
    {
        OdbcCommand command = new OdbcCommand();
        OdbcTransaction transaction = null;

        // Set the Connection to the new OdbcConnection.
        command.Connection = connection;

        // Open the connection and execute the transaction.
        try
        {
            connection.Open();

            // Start a local transaction
            transaction = connection.BeginTransaction();

            // Assign transaction object for a pending local transaction.
            command.Connection = connection;
            command.Transaction = transaction;

            // Execute the commands.
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')";
            command.ExecuteNonQuery();
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')";
            command.ExecuteNonQuery();

            // Commit the transaction.
            transaction.Commit();
            Console.WriteLine("Both records are written to database.");
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
            try
            {
                // Attempt to roll back the transaction.
                transaction.Rollback();
            }
            catch
            {
                // Do nothing here; transaction is not active.
            }
        }
        // The connection is automatically closed when the
        // code exits the using block.
    }
}

Public Sub ExecuteTransaction(ByVal connectionString As String)

    Using connection As New OdbcConnection(connectionString)
        Dim command As New OdbcCommand()
        Dim transaction As OdbcTransaction

        ' Set the Connection to the new OdbcConnection.
        command.Connection = connection

        ' Open the connection and execute the transaction.
        Try
            connection.Open()

            ' Start a local transaction.
            transaction = connection.BeginTransaction()

            ' Assign transaction object for a pending local transaction.
            command.Connection = connection
            command.Transaction = transaction

            ' Execute the commands.
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (100, 'Description')"
            command.ExecuteNonQuery()
            command.CommandText =
                "Insert into Region (RegionID, RegionDescription) VALUES (101, 'Description')"
            command.ExecuteNonQuery()

            ' Commit the transaction.
            transaction.Commit()
            Console.WriteLine("Both records are written to database.")

        Catch ex As Exception
            Console.WriteLine(ex.Message)
            ' Try to rollback the transaction
            Try
                transaction.Rollback()

            Catch
                ' Do nothing here; transaction is not active.
            End Try
        End Try
        ' The connection is automatically closed when the
        ' code exits the Using block.
    End Using
End Sub

注解

事务只能从挂起状态回滚， (调用 之后 BeginTransaction ，但在调用) 之前 Commit 。 如果事务在之前释放 Commit 或 Rollback 被调用，则会回滚该事务。

另请参阅

• 执行事务