Inheritance - abstract methods & attribute.

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Hello.

I want to enforce programmers, who use a specific class, to override specific methods.

For that - I declare the main object as abstract object, and the some of methods as abstract.

But, what if those methods has [datamemberAttribute] - When I add new inherited function, the [datamemberattribute] is not copied - How can I make that [datamemberAttribute] (and any member farther) will be copied either.

Thanks :)

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Ivan (Vanya) Kashperuk on at

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I don't think that is possible in X++ at the moment.

On a side note - why don't you uses an interface instead of an abstract class?

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Martin Dráb 237,878 Most Valuable Professional on at

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First of all, what's the problem you're solving? I tried it with a custom service and it works fine; AX obviously look at parent classes for attributes. If you're reading attribute by yourself, you'll have to deal with base classes by yourself too.

Nevertheless you can also design your class is such a way that the data member doesn't get overridden. In the example below, the data member is final and it delegates the work to a protected abstract method which will be implemented in a subclass.

class BaseClass { [DataMemberAttribute] public final str parmItem(str _item = item) { if (prmIsDefault(_item)) { return parmItemCore(); } else { return parmItemCode(_item); } } protected abstract str parmItemCore(str _item = item) { } }

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Community Member on at

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I want to make a general class:

abstract Class MyClass extends SysAttribute

and a method :

[DatamemberAttribute('MyMethod')] abstract str parmMyMethod(str _value) { // .... do something }

When I inherit MyClass, and right click on class + "New" + "method" is see parmMyMethod method.

Choosing it will not add also [DataMemberAttribute] clause.

How can I also add by the above way (right click on class + "New" + "method" is see parmMyMethod method) and the [DataMemberAttribute] will be copied also.

Thanks :)

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Martin Dráb 237,878 Most Valuable Professional on at

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That's the correct and expected behavior. If you want some other behavior, write a code generator. Nevertheless I would recommend following my previous reply:

Review whether you need to specify the attribute in both methods (in the base and the child class) at all. Custom services doesn't require that (and I believe, but I didn't explicitly test, that neither SSRS). Unless you explain why you need, I suspect you're wasting time with a wrong problem.

You can avoid the whole problem by overriding a normal method and keeping data members untouched, as shown in the example above.

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Deepak Agarwal 8,602 on at

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Maybe this will help

theaxapta.blogspot.in/.../abstract-class-and-abstract-method-in.html

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