DependentTransaction 类

定义

public ref class DependentTransaction sealed : System::Transactions::Transaction

public sealed class DependentTransaction : System.Transactions.Transaction

[System.Serializable]
public sealed class DependentTransaction : System.Transactions.Transaction

type DependentTransaction = class
    inherit Transaction

[<System.Serializable>]
type DependentTransaction = class
    inherit Transaction

Public NotInheritable Class DependentTransaction
Inherits Transaction

继承

Object

Transaction

DependentTransaction

属性

SerializableAttribute

示例

以下示例演示如何创建依赖事务。

static void Main(string[] args)
{
    try
    {
        using (TransactionScope scope = new TransactionScope())
        {
            // Perform transactional work here.

            //Queue work item
            ThreadPool.QueueUserWorkItem(new WaitCallback(WorkerThread), Transaction.Current.DependentClone(DependentCloneOption.BlockCommitUntilComplete));

            //Display transaction information
            Console.WriteLine("Transaction information:");
            Console.WriteLine("ID:             {0}", Transaction.Current.TransactionInformation.LocalIdentifier);
            Console.WriteLine("status:         {0}", Transaction.Current.TransactionInformation.Status);
            Console.WriteLine("isolationlevel: {0}", Transaction.Current.IsolationLevel);

            //Call Complete on the TransactionScope based on console input
            ConsoleKeyInfo c;
            while (true)
            {
                            Console.Write("Complete the transaction scope? [Y|N] ");
                c = Console.ReadKey();
                Console.WriteLine();

                if ((c.KeyChar == 'Y') || (c.KeyChar == 'y'))
                {
                    //Call complete on the scope
                    scope.Complete();
                    break;
                }
                else if ((c.KeyChar == 'N') || (c.KeyChar == 'n'))
                {
                    break;
                }
            }
        }
    }
    catch (System.Transactions.TransactionException ex)
    {
        Console.WriteLine(ex);
    }
    catch
    {
        Console.WriteLine("Cannot complete transaction");
        throw;
    }
}

private static void WorkerThread(object transaction)
{
    //Create a DependentTransaction from the object passed to the WorkerThread
    DependentTransaction dTx = (DependentTransaction)transaction;

    //Sleep for 1 second to force the worker thread to delay
    Thread.Sleep(1000);

    //Pass the DependentTransaction to the scope, so that work done in the scope becomes part of the transaction passed to the worker thread
    using (TransactionScope ts = new TransactionScope(dTx))
    {
        //Perform transactional work here.

        //Call complete on the transaction scope
        ts.Complete();
    }

    //Call complete on the dependent transaction
    dTx.Complete();
}

Public Shared Sub Main()
    Try
        Using scope As TransactionScope = New TransactionScope()

            'Perform transactional work here.

            'Queue work item
            ThreadPool.QueueUserWorkItem(AddressOf WorkerThread, Transaction.Current.DependentClone(DependentCloneOption.BlockCommitUntilComplete))

            'Display transaction information
            Console.WriteLine("Transaction information:")
            Console.WriteLine("ID:             {0}", Transaction.Current.TransactionInformation.LocalIdentifier)
            Console.WriteLine("status:         {0}", Transaction.Current.TransactionInformation.Status)
            Console.WriteLine("isolationlevel: {0}", Transaction.Current.IsolationLevel)

            'Call Complete on the TransactionScope based on console input
            Dim c As ConsoleKeyInfo
            While (True)

                Console.Write("Complete the transaction scope? [Y|N] ")
                c = Console.ReadKey()
                Console.WriteLine()
                If (c.KeyChar = "Y") Or (c.KeyChar = "y") Then
                    scope.Complete()
                    Exit While
                ElseIf ((c.KeyChar = "N") Or (c.KeyChar = "n")) Then
                    Exit While
                End If
            End While
        End Using

    Catch ex As TransactionException
        Console.WriteLine(ex)
    Catch
        Console.WriteLine("Cannot complete transaction")
        Throw
    End Try
End Sub

Public Shared Sub WorkerThread(ByVal myTransaction As Object)

    'Create a DependentTransaction from the object passed to the WorkerThread
    Dim dTx As DependentTransaction
    dTx = CType(myTransaction, DependentTransaction)

    'Sleep for 1 second to force the worker thread to delay
    Thread.Sleep(1000)

    'Pass the DependentTransaction to the scope, so that work done in the scope becomes part of the transaction passed to the worker thread
    Using ts As TransactionScope = New TransactionScope(dTx)
        'Perform transactional work here.

        'Call complete on the transaction scope
        ts.Complete()
    End Using

    'Call complete on the dependent transaction
    dTx.Complete()
End Sub

注解

DependentTransaction是使用 DependentClone 方法创建的 对象的克隆Transaction。 其唯一目的是允许应用程序休息，并保证当仍在对事务 (（例如，在工作线程) ）上执行工作时，事务无法提交。

当克隆事务中完成的工作最终完成并准备好提交时，可以使用 方法通知事务 Complete 创建者。 因此，可以保留数据的一致性和正确性。

枚举 DependentCloneOption 用于确定提交时的行为。 此行为控制允许应用程序休息，并提供并发支持。 有关如何使用此枚举的详细信息，请参阅 使用 DependentTransaction 管理并发。

线程安全性

此类型是线程安全的。

另请参阅

• 使用 DependentTransaction 管理并发