迁移序列化对象到新版本 [英] Migrate serialized objects to new version

问题描述

我想序列化对象迁移我以前在数据库中新的模式。

I would like to migrate me previously serialized objects in database to new schema.

我以前的对象。

Public interface MyReport
{

    string Id { get; set;}

    string Name { get; set;}

    Dictionary<string, string> PropColl { get; set;}
}

但由于种种原因，我们不得不作出界面的改变。

But for some reasons we had to make interface changes

Public interface IMarkme
{
}

Public interface MyReport<T> where T : Imarkme
{

    string Id { get; set;}

    string Name { get; set;}

    T ExtendedProp { get; set;}
}

Public NewProp : Imarkme
{
    /// some code here 
}

因此，大家可以看到我的接口已被修改，我想迁移是基于MyReport其序列化到MyReport
我的序列化对象有人可以提供我一些输入作为我的目标应该是写一个可以帮助我实现迁移我的序列化对象，以新的修改界面的版本是什么样的效用。

So as you can see my interface has been modified and I would like to migrate my serialized objects which were serialized based on MyReport to MyReport Can someone provide me some input as what kind of utility I should aim to write which can help me achieve migrating my serialized object to new modified interface version.

谢谢，
AG

Thanks, AG

推荐答案

其实我已经做了类似的事情最近，我在那里已经创建了一个简单的控制台应用程序能够变换一些序列化对象从一个版本到另一个。我只是简单地使用DLL和反射的两个版本读取和写入不同属性的值。也许你会发现这是很有帮助的灵感;）

I have actually done something similar recently, where I have created a simple console application to be able to transform some serialized objects from one version to another. I have simply used both versions of dlls and reflection to read and write the values of different properties. Probably you'll find this helpful as an inspiration ;)

static void Main(string[] args)
    {
        object test;

        AppDomain.CurrentDomain.AssemblyResolve += domain_AssemblyResolve;


        using (var con = new SqlConnection(connectionString))
        {
            using (var cmd = new SqlCommand())
            {
                cmd.CommandText = "select top 1 Data_Blob from dbo.Serialized";
                cmd.CommandType = CommandType.Text;
                cmd.Connection = con;

                con.Open();
                var blob = (byte[])cmd.ExecuteScalar();

                var bf = new BinaryFormatter();
                var stream = new MemoryStream(blob);
                bf.AssemblyFormat = FormatterAssemblyStyle.Full;
                test = bf.Deserialize(stream);
            }
        }

        var objNewVersion = Activator.CreateInstance(Type.GetType("ObjectGraphLibrary.Test, ObjectGraphLibrary, Version=1.0.0.10, Culture=neutral, PublicKeyToken=33c7c38cf0d65826"));


        var oldType = test.GetType();
        var newType = objNewVersion.GetType();

        var oldName = (string) oldType.GetProperty("Name").GetValue(test, null);
        var oldAge = (int) oldType.GetProperty("Age").GetValue(test, null);

        newType.GetProperty("Name").SetValue(objNewVersion, oldName, null);
        newType.GetProperty("DateOfBirth").SetValue(objNewVersion, DateTime.Now.AddYears(-oldAge), null);


        Console.Read();
    }

    static Assembly domain_AssemblyResolve(object sender, ResolveEventArgs args)
    {
        var assName = new AssemblyName(args.Name);

        var uriBuilder = new UriBuilder(Assembly.GetExecutingAssembly().CodeBase);
        var assemblyPath = Uri.UnescapeDataString(uriBuilder.Path);
        var codeBase = Path.GetDirectoryName(assemblyPath);

        var assPath = Path.Combine(codeBase, string.Format("old\\{0}.{1}.{2}.{3}\\{4}.dll", assName.Version.Major,
                                                 assName.Version.Minor, assName.Version.Build,
                                                 assName.Version.Revision, assName.Name));

        return File.Exists(assPath) ? Assembly.LoadFile(assPath) : null;
    }

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