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C # - extended inheritance

Please take a look at my class structure. I think I would like to enjoy inheritance more than is possible.

First there is a base abstract class:

public abstract class PolicyDetailed
{
    internal abstract DataContainer GetActiveAsset();
}

Next, there is another abstract class that is generic:

public abstract class PolicyDetailed<T> : PolicyDetailed where T : DataContainer
{
    internal new abstract T GetActiveAsset();
}

Finally, there is a certain class of policy. AccidentContainer inherits from DataContainer:

public class PolicyAccident : PolicyDetailed<AccidentContainer>
{
    internal override AccidentContainer GetActiveAsset()
    {
        return null;
    }
}

At compile time, I get the following error:

'PolicyAccident' does not implement inherited abstract member 'PolicyDetailed.GetActiveAsset()'

, , . , , : (, PolicyAccident, PolicyTravel ..), PolicyDetailed DataContainer (AccidentContainer, TravelContainer ..). GetActiveAsset , PolicyDetailed. , Datacontainer. ?

+5
1

, - , .

:

  • . PolicyDetailed<T>, :

    public abstract class PolicyDetailed
{
    internal abstract DataContainer GetActiveAsset();
}

public abstract class PolicyDetailed<T> : PolicyDetailed where T : DataContainer
{
    internal abstract T GetActiveAssetGeneric();

    internal override DataContainer GetActiveAsset()
    {
        return GetActiveAssetGeneric();
    }
}

public class PolicyAccident : PolicyDetailed<AccidentContainer>
{
    internal override AccidentContainer GetActiveAssetGeneric()
    {
        return null;
    }    
}

  • , . :

    public class DataContainer {}
public class AccidentContainer : DataContainer{}

public abstract class PolicyDetailed
{
    internal abstract DataContainer GetActiveAsset();
}

// This only exists to satisfy the base class abstract member,
// but at the same time allowing PolicyDetailed<T> to introduce
// a new member with the same name.
public abstract class PolicyDetailedBridge<T> : PolicyDetailed
    where T : DataContainer
{
    protected abstract T GetActiveAssetGeneric();

    internal override DataContainer GetActiveAsset()
    {
        return GetActiveAssetGeneric();
    }
}

public abstract class PolicyDetailed<T> : PolicyDetailedBridge<T>
    where T : DataContainer
{
    protected sealed override T GetActiveAssetGeneric()
    {
        // Call the *new* abstract method. Eek!
        return GetActiveAsset();
    }

    internal abstract new T GetActiveAsset();
}

public class PolicyAccident : PolicyDetailed<AccidentContainer>
{
    internal override AccidentContainer GetActiveAsset()
    {
        return null;
    }            
}

  • PolicyDetailed , , - .

+6

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