C#中的可交易对象？

Question

看代码:

class MyClass {  public static int g=1;}

using (TransactionScope tsTransScope = new TransactionScope())
{
    //Do stuff here
    MyClass.g=999;
    tsTransScope.Complete();
}

• 看看" Do stuff here "部分:我可以在那里写什么类型的对象,这样它们可以成为可交易的？我已经知道我可以编写ADO命令,并且在需要时它们将被回滚/提交.但是通过C#POV:一个类必须具有什么实现才能成为可交易的(实现一些接口或什么？)

• 如果它是一个TransactionScope 正如它所调用的那样,在一个using子句中(最后是try +),逻辑说如果有回滚:MyClass.g应该返回其值为1的值.这不会发生.所以我想这与第一个问题有关.如何使MyClass成为可交易的？

Answer 1

你应该实现System.Transactions.IEnlistmentNotification的接口,这个文章,这可以帮助你

对于现成的事务性内存存储,有(软件事务内存)和STM.NET它不是最终的东西,但微软正在努力!

一个小例子:

using System.IO;
using System.Text;
using System.Transactions;

namespace Sakher.Transactions
{
    public class TsansactionalFileWriter
    {
        private FileTransactionEnlistment fileTransactionEnlistment = new FileTransactionEnlistment();
        public TsansactionalFileWriter(string filePath)
        {
            fileTransactionEnlistment.FilePath = filePath;
            Transaction.Current.EnlistVolatile(fileTransactionEnlistment, EnlistmentOptions.None);
        }

        public void AppendText(string text)
        {
            fileTransactionEnlistment.Content.Append(text);
        }

        public void WriteAllText(string text)
        {
            fileTransactionEnlistment.Content = new StringBuilder(text);
        }
    }

    public class FileTransactionEnlistment : IEnlistmentNotification
    {
        public string FilePath { get; set; }
        public StringBuilder Content { get; set; }

        public FileTransactionEnlistment()
        {
            Content = new StringBuilder();
        }

        public void Commit(Enlistment enlistment)
        {
            File.WriteAllText(FilePath, Content.ToString());
        }

        public void InDoubt(Enlistment enlistment)
        {

        }

        public void Prepare(PreparingEnlistment preparingEnlistment)
        {
            //You can create the file here
            preparingEnlistment.Prepared();
        }

        public void Rollback(Enlistment enlistment)
        {
            //Do ssomething when the transaction is rolled-back (You may delete the file if you have created it!)
        }
    }

}

使用代码:

        using (TransactionScope tr = new TransactionScope())
        {
            TsansactionalFileWriter writer = new TsansactionalFileWriter("c:\\myFile.txt");
            writer.AppendText("sdfgssdfgsdf");
            tr.Complete();
        }

*EDTI:为ROYI添加G保持者:)*

using System.Transactions;

namespace Sakher.Transactions
{
    public class  Royi_s_gReturnerClass 
    {
        private GReturnerEnlistment fileTransactionEnlistment = new GReturnerEnlistment();
        public Royi_s_gReturnerClass()
        {
            Transaction.Current.EnlistVolatile(fileTransactionEnlistment, EnlistmentOptions.None);
        }
    }

    public class GReturnerEnlistment : IEnlistmentNotification
    {
        public int GOldValue { get; set; }

        public GReturnerEnlistment()
        {
            GOldValue = MyClass.g;
        }

        public void Commit(Enlistment enlistment)
        {

        }

        public void InDoubt(Enlistment enlistment)
        {

        }

        public void Prepare(PreparingEnlistment preparingEnlistment)
        {
            preparingEnlistment.Prepared();
        }

        public void Rollback(Enlistment enlistment)
        {
            MyClass.g = GOldValue;
        }
    }

}

您的代码将是:

class MyClass {  public static int g=1;}

using (TransactionScope tsTransScope = new TransactionScope())
{
    Royi_s_gReturnerClass returner = new Royi_s_gReturnerClass();
    //Do stuff here
    MyClass.g=999;
    tsTransScope.Complete();
}