Delegates concept in D365

Delegates allow us to access elements in higher models form a lower model. With a model split a hierarchy has been created where a higher model can take dependencies and access elements in the models below, but not in models above.

While the model split provides many benefits, it creates a problem when trying to access elements defined in higher models. Delegates are the recommended method for accessing elements in higher models from a lower model. Delegates are very similar to events in that when a delegate instance is invoked, a handler with compatible signature code is executed. This permits higher layer code, the handler, to be called by lower layer code, the delegate instance.

Delegate methods serve as a means for defining a contract between the delegate instance and the delegate handler. A delegate takes no action itself. This is enforced by having a void type and having no code in the method.

A delegate declaration must have three things:

• The delegate keyword
• Type void
• Empty method

For demo purpose, please refer Using Delegates in AX7 / D365 blog post that can describe how we can use delegates using X++.