c＃从泛型类继承

Question

Let me describe the logic and then class structure. There are objects and all object must inherit from ConfigurationObjectBase. Each object must be owned by Manager and all Managers must be derived from ConfigurationObjectManagerBase. When a new instance of object created, one of the constructor must accept instance of Manager and that instance of Manager must add that instance of object into it's property called ChildObjects. Below is sample of classes. could you pls help to correct in below code acording above business rule? Thanks.

public class ConfigurationObjectBase<ObjectType>
{
    public ConfigurationObjectBase(ConfigurationObjectManagerBase<ObjectType> ownerManager)
    {
        ownerManager.ChildObjects.Add(this);
    }
}


public class ConfigurationObjectManagerBase<ObjectType>
{
    public ConfigurationObjectManagerBase()
    {
        ChildObjects = new List<ObjectType>();
    }

    public List<ObjectType> ChildObjects { get; set; }
}

public class Catalog : ConfigurationObjectBase<Catalog>
{
    public Catalog(CatalogManager ownerManager) : base(???)
    {

    }
}

public class CatalogManager : ConfigurationObjectManagerBase<CatalogManager>
{
    public CatalogManager() : base()
    {
    }
}

Answer 1

There are two issues in your code:

• CatalogManager should inherit from ConfigurationObjectManagerBase<Catalog> , not ConfigurationObjectManagerBase<CatalogManager>
• ChildObjects should probably be a list of ConfigurationObjectBase<ObjectType> , rather than a list of ObjectType (otherwise you can't add a ConfigurationObjectBase<ObjectType> to it)

So the code should probably look like this:

public class ConfigurationObjectBase<ObjectType>
{
    public ConfigurationObjectBase(ConfigurationObjectManagerBase<ObjectType> ownerManager)
    {
        ownerManager.ChildObjects.Add(this);
    }
}


public class ConfigurationObjectManagerBase<ObjectType>
{
    public ConfigurationObjectManagerBase()
    {
        ChildObjects = new List<ConfigurationObjectBase<ObjectType>>();
    }

    public List<ConfigurationObjectBase<ObjectType>> ChildObjects { get; set; }
}

public class Catalog : ConfigurationObjectBase<Catalog>
{
    public Catalog(CatalogManager ownerManager) : base(ownerManager)
    {

    }
}

public class CatalogManager : ConfigurationObjectManagerBase<Catalog>
{
    public CatalogManager()
    {
    }
}

Also, you don't need to call the default base class constructor ( base() ), it's done implicitly by the compiler.