TransactionScope 类

定义

使代码块成为事务性代码。Makes a code block transactional. 此类不能被继承。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
继承
TransactionScope
实现

示例

下面的示例演示如何使用TransactionScope类定义代码块以参与事务。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

注解

基础结构提供基于类的Transaction显式编程模型,以及使用TransactionScope类的隐式编程模型,在该模型中,事务由基础结构自动管理。 System.TransactionsThe 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.

重要

建议使用TransactionScope类创建隐式事务,以便自动管理环境事务上下文。We recommend that you create implicit transactions using the TransactionScope class, so that the ambient transaction context is automatically managed for you. 还应将TransactionScopeDependentTransaction类用于需要跨多个函数调用或多个线程调用使用同一事务的应用程序。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. 有关此模型的详细信息,请参阅使用事务范围实现隐式事务主题。For more information on this model, see the Implementing An Implicit Transaction Using Transaction Scope topic. 有关编写事务应用程序的详细信息,请参阅编写事务应用程序For more information on writing a transactional application, see Writing A Transactional Application.

TransactionScopenew按语句实例化时,事务管理器会确定要参与的事务。Upon instantiating a TransactionScope by the new statement, the transaction manager determines which transaction to participate in. 一旦确定,该范围将始终参与该事务。Once determined, the scope always participates in that transaction. 此决策基于两个因素:是否存在环境事务以及构造函数中 TransactionScopeOption 参数的值。The decision is based on two factors: whether an ambient transaction is present and the value of the TransactionScopeOption parameter in the constructor. 环境事务是您的代码在其中执行的事务。The ambient transaction is the transaction your code executes in. 可通过调用 Transaction.Current 类的静态 Transaction 属性,获取对环境事务的引用。You can obtain a reference to the ambient transaction by calling the static Transaction.Current property of the Transaction class. 有关如何使用此参数的详细信息,请参阅使用事务范围实现隐式事务主题中的 "事务流管理" 一节。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.

如果事务范围内(即在TransactionScope对象的初始化与调用其Dispose方法之间)未发生异常,则允许作用域参与的事务继续。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. 如果事务范围内发生异常,则将回滚其参与的事务。If an exception does occur within the transaction scope, the transaction in which it participates will be rolled back.

当应用程序完成要在事务中执行的所有工作时,只应调用Complete方法一次,以通知事务管理器可以提交事务。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. 未能调用此方法将中止事务。Failing to call this method aborts the transaction.

Dispose方法的调用将标记事务范围的末尾。A call to the Dispose method marks the end of the transaction scope. 在调用此方法之后所发生的异常不会影响事务。Exceptions that occur after calling this method may not affect the transaction.

如果修改范围Current内的值,则在Dispose调用时会引发异常。If you modify the value of Current inside a scope, an exception is thrown when Dispose is called. 但是,在范围结束时,将还原以前的值。However, at the end of the scope, the previous value is restored. 此外,如果您在Dispose Current创建了事务的事务范围内调用,则事务将在范围结束时中止。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.

构造函数

TransactionScope()

初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class.

TransactionScope(Transaction)

初始化 TransactionScope 类的新实例,并将指定的事务设置为环境事务,以便该范围中进行的事务性工作使用此事务。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)

使用指定的超时时间值初始化 TransactionScope 类的新实例,并将指定的事务设置为环境事务,以便该范围中进行的事务性工作使用此事务。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)

使用指定的超时时间值和 COM+ 互操作性要求初始化 TransactionScope 类的新实例,并将指定的事务设置为环境事务,以便该范围中进行的事务性工作使用此事务。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)

[在 .NET Framework 4.5.1 和更高版本中受支持][Supported in the .NET Framework 4.5.1 and later versions] 使用指定的超时时间值初始化 TransactionScope 类的新实例,并将指定的事务设置为环境事务,以便该范围中进行的事务性工作使用此事务。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)

[在 .NET Framework 4.5.1 和更高版本中受支持][Supported in the .NET Framework 4.5.1 and later versions] 初始化 TransactionScope 类的新实例,并将指定的事务设置为环境事务,以便该范围中进行的事务性工作使用此事务。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)

使用指定的异步流选项初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class with the specified asynchronous flow option.

TransactionScope(TransactionScopeOption)

以指定的要求初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class with the specified requirements.

TransactionScope(TransactionScopeOption, TimeSpan)

以指定的超时时间值和要求初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class with the specified timeout value and requirements.

TransactionScope(TransactionScopeOption, TimeSpan, TransactionScopeAsyncFlowOption)

以指定的超时值、要求和异步流选项初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class with the specified timeout value, requirements, and asynchronous flow option.

TransactionScope(TransactionScopeOption, TransactionOptions)

以指定的要求初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class with the specified requirements.

TransactionScope(TransactionScopeOption, TransactionOptions, EnterpriseServicesInteropOption)

使用指定的范围和 COM+ 互操作性要求以及事务选项初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class with the specified scope and COM+ interoperability requirements, and transaction options.

TransactionScope(TransactionScopeOption, TransactionOptions, TransactionScopeAsyncFlowOption)

[在 .NET Framework 4.5.1 和更高版本中受支持][Supported in the .NET Framework 4.5.1 and later versions] 以指定的要求和异步流选项初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class with the specified requirements and asynchronous flow option.

TransactionScope(TransactionScopeOption, TransactionScopeAsyncFlowOption)

以指定的要求和异步流选项初始化 TransactionScope 类的新实例。Initializes a new instance of the TransactionScope class with the specified requirements and asynchronous flow option.

方法

Complete()

指示范围中的所有操作都已成功完成。Indicates that all operations within the scope are completed successfully.

Dispose()

结束事务范围。Ends the transaction scope.

Equals(Object)

确定指定的对象是否等于当前对象。Determines whether the specified object is equal to the current object.

(继承自 Object)
GetHashCode()

作为默认哈希函数。Serves as the default hash function.

(继承自 Object)
GetType()

获取当前实例的 TypeGets the Type of the current instance.

(继承自 Object)
MemberwiseClone()

创建当前 Object 的浅表副本。Creates a shallow copy of the current Object.

(继承自 Object)
ToString()

返回表示当前对象的字符串。Returns a string that represents the current object.

(继承自 Object)

适用于

线程安全性

此类型是线程安全的。This type is thread safe.

另请参阅