To choose the appropriate programming model and tools for your business application development, you must first identify the basic development patterns that can be combined to create your application. Development patterns are the building blocks of any business application, and they fall into the following categories:
- External application module development
- Custom dedicated applications development
- Report development
- Enterprise Portal Web application development
Although real-life applications rarely fit neatly into a single development pattern, it is possible to identify large parts of an application that fit into one of these development patterns. It is important to understand these pattern categories, because each of the following programming models in Microsoft Dynamics AX is best suited for to one of these development patterns. The following sections provide definitions and an example of each development pattern.
Customization is the development pattern in which you create new functionality by altering, extending, or enhancing the functionality in the shipped product.
Alterations to the base functionality are achieved by changing the metadata and source code of the base application. This is done through the alteration of artifacts such as X++ classes, tables, and Visual Studio projects in a higher layer, such as, for example, the ISV layer or the VAR layer. The unique layering feature of Microsoft Dynamics AX enables the system to synthesize the final application logic to be executed at run-time by aggregating the metadata and code modifications across all the layers. You should be aware that this layer-based customization capability is applicable to all artifacts stored in the Microsoft Dynamics AX model store, including the Visual Studio project artifacts.
Extensions to functionality are achieved by incrementally increasing base functionality by adding to the source code in the business logic of the base application.
Enhancements to the application are achieved by adding new functionality originally unavailable in the base application. Typically, an enhancement is larger in scope than an alteration or extension. An example of customizations would be a scenario in which a new regulation from the government requires the existing sales tax computation business logic to reflect the inclusion of an additional “environmental sustainability tax” component. If the calculation behind this new component is straightforward and simple, you can simply alter the base tax computation logic in a higher layer and directly implement the required source code changes. However, if this tax module has business rules that are more complex, you should consider enhancing the base product with a new tax engine component that implements these requirements.
Integration is the development pattern that involves enabling existing applications (not written exclusively for Microsoft Dynamics AX) to interact and work with Microsoft Dynamics AX across process boundaries. An example of integration is when a value added reseller (VAR) integrates with an existing legacy Customer Relationship Management (CRM) system to synchronize the customer list between Microsoft Dynamics AX and the legacy CRM system.
3. External application module development
The development pattern for application modules that run out-of-process of the AOS server or Microsoft Dynamics AX client processes.
Custom dedicated application development is the development pattern that builds a new, custom external application/client that accesses functionality and data in the Microsoft Dynamics AX system. These applications can span multiple platforms and programming languages.
An example of custom dedicate application development is creating a Windows Phone 7 application to view open sales orders in Microsoft Dynamics AX.
Report development is the development pattern that creates custom reports and customizes any out of the box reports for the Microsoft Dynamics AX platform.
Enterprise Portal web application development is the development pattern that creates web applications specifically built on the Microsoft Dynamics AX Enterprise Portal development framework.
An example of web application development is creating an Enterprise Portal-based employee self-service page to enter time-sheet data.