.net - 混合MarshalByRefObject和Serializable

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我正在设计我的第一个使用AppDomains的应用程序，我想知道当您在未实现MarshalByRefObject的可序列化对象中放置对MarshalByRefObjects的引用时会发生什么，因为到目前为止我找不到关于此主题的任何文档。

例如，如果我尝试返回List<MBR>，而MBR : MarshalByRefObject跨越AppDomain边界，会发生什么情况？我是否获得了List<MBR>的副本，其中每个MBR是原始对象的TransparentProxy？是否有关于混合这两种机制的技术细节的文档？

最佳答案

我只是使用List<MBR>进行了快速测试，它似乎按我希望的那样工作:

public class MBR : MarshalByRefObject
{
    List<MBR> _list;
    public MBR() { _list = new List<MBR> { this }; }
    public IList<MBR> Test() { return _list; }
    public int X { get; set; }
}

// Later...
var mbr = AppDomainStarter.Start<MBR>(@"C:\Program Files", "test", null, true);
var list = mbr.Test();
list[0].X = 42;
list.Clear();
Debug.WriteLine(string.Format("X={0}, Count={1}", mbr.X, mbr.Test().Count));

输出为X=42, Count=1，调试器显示List<MBR>包含__TransparentProxy。很明显，MarshalByRefObject已成功通过引用在另一个按值编码的对象内进行编码。

如果有人可以找到，我仍然希望查看文档或技术详细信息。

对于任何好奇的人，我都编写了这个方便的沙盒AppDomainStarter:

/// <summary><see cref="AppDomainStarter.Start"/> starts an AppDomain.</summary>
public static class AppDomainStarter
{
    /// <summary>Creates a type in a new sandbox-friendly AppDomain.</summary>
    /// <typeparam name="T">A trusted type derived MarshalByRefObject to create
    /// in the new AppDomain. The constructor of this type must catch any
    /// untrusted exceptions so that no untrusted exception can escape the new
    /// AppDomain.</typeparam>
    /// <param name="baseFolder">Value to use for AppDomainSetup.ApplicationBase.
    /// The AppDomain will be able to use any assemblies in this folder.</param>
    /// <param name="appDomainName">A friendly name for the AppDomain. MSDN
    /// does not state whether or not the name must be unique.</param>
    /// <param name="constructorArgs">Arguments to send to the constructor of T,
    /// or null to call the default constructor. Do not send arguments of
    /// untrusted types this way.</param>
    /// <param name="partialTrust">Whether the new AppDomain should run in
    /// partial-trust mode.</param>
    /// <returns>A remote proxy to an instance of type T. You can call methods
    /// of T and the calls will be marshalled across the AppDomain boundary.</returns>
    public static T Start<T>(string baseFolder, string appDomainName,
        object[] constructorArgs, bool partialTrust)
        where T : MarshalByRefObject
    {
        // With help from http://msdn.microsoft.com/en-us/magazine/cc163701.aspx
        AppDomainSetup setup = new AppDomainSetup();
        setup.ApplicationBase = baseFolder;

        AppDomain newDomain;
        if (partialTrust) {
            var permSet = new PermissionSet(PermissionState.None);
            permSet.AddPermission(new SecurityPermission(SecurityPermissionFlag.Execution));
            permSet.AddPermission(new UIPermission(PermissionState.Unrestricted));
            newDomain = AppDomain.CreateDomain(appDomainName, null, setup, permSet);
        } else {
            newDomain = AppDomain.CreateDomain(appDomainName, null, setup);
        }
        return (T)Activator.CreateInstanceFrom(newDomain,
            typeof(T).Assembly.ManifestModule.FullyQualifiedName,
            typeof(T).FullName, false,
            0, null, constructorArgs, null, null).Unwrap();
    }
}