Serialize List<ICustomClass> to xml?

Question

I have the following code files:

public interface IMod
{
    string Name { get; set; }
    string Description { get; set; }
    bool Enabled { get; set; }
    List<IClassFile> ClassFiles { get; set; }
}
public interface IClassFile
{
    string Path { get; set; }
    string FileName { get; set; }
    bool Enabled { get; set; }
}
public class ClassFile : IClassFile
{
    public string Path { get; set; }
    public string FileName { get { return System.IO.Path.GetFileName(Path); } }
    public bool Enabled { get; set; }

    ....
}
public class ZippedMod : IMod
{
    public string Name { get; set; }
    public string Description { get; set; }
    public bool Enabled { get; set; }
    public List<IClassFile> ClassFiles { get; set; }

    ....
}
public class ConfigurationBlock
{
    public List<IMod> Mods { get; set; }

    ....
}

Throughout the course of my program, I add a few ZippedMods to the ConfigurationBlock, but now I want to serialize them. I tried doing:

using (var stream = new StreamWriter("config.xml"))
{
    var ser = new XmlSerializer(typeof(ConfigurationBlock));
    ser.Serialize(stream, configBlock);
}

But I get this error:

There was an error reflecting type 'MinecraftModManager.ConfigurationBlock'.
|-Inner Exception:
      Cannot serialize member 'MinecraftModManager.ConfigurationBlock.Mods' of type 'System.Collections.Generic.List`1[[MinecraftModManager.IMod, MinecraftModManager, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]', see inner exception for more details.
      |-Inner Exception:
            Cannot serialize member MinecraftModManager.ConfigurationBlock.Mods of type MinecraftModManager.IMod because it is an interface.

Help?

Answer 1

You can't serialize an interface due to the abstract nature of them. Lots of concrete types can implement the same interface, so it creates an ambiguity. You must use a concrete type.