Re: Factory method question

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On Mar 12, 7:07 pm, "Paul E Collins" <find_my_real_addr...@xxxxxxx>
wrote:
<jonathan.broder...@xxxxxxxxx> wrote:
I was hoping to avoid programming directly to the factory instances
and rather to an interface or abstract class. Is that correct or am I
missing something?

Yes, my suggestion means you'd be programming to concrete classes.

Could you post a short, simplified version of your code, or at least
explain what you're trying to model? Otherwise, it's hard to tell what
approach might be suitable.

Eq.

The application I'm creating is a web application. I would guess 90%
of the processing is loading/saving/deleting/updating from an SQL
database. So there's not much processing going on.

Here's some sample code thats sort of like my problem:

public interface IConditional
{
bool IsMatch(string[] data);
}

public class FieldConditional : IConditional
{
public FieldConditional(IField field)
{
... code
}

bool IsMatch(string[] data)
{
... code
}
}

public class DateConditional : IConditional
{
public FieldConditional(DateTime date)
{
... code
}

bool IsMatch(string[] data)
{
... code
}
}


These objects (FieldCondtional and DateConditional) are saved in the
database with a unique
ID between them. I know I can do this:

IConditional c = ConditionalFactory.Load(id);

Is there a way i could do something like this:

IConditional c = ConditionalFactory.Create(<data>);

That way I let the Factory know which object to create and how. I Dont
want to have to do soemthing like this:

IConditional c = ConditionalFactory.CreateField(<data>);
or...
IConditional c = ConditionalFactory.CreateDate(<data>);

The creating part I'm not so sure how to do.
.

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