Before starting the actual migration process, it is necessary for a developer or project manager to assess the application under consideration. The objective of this phase is to understand the extent of changes required for migration and come up with an appropriate project plan for the migration.
Considering the nature of the application and the amount of changes to be made in the Visual Basic 6.0 application, it can be classified in one of the following three categories:
Applications with the following features are considered simple and can be migrated easily:
Dynamic-link libraries (DLLs)
Application with only Forms or MDI Forms
Applications with the following features can be considered of medium complexity and can be migrated with changes:
Data binding using ActiveX Data Objects (ADO)
Applications that require extensive code changes can be regarded as advanced applications:
ActiveX Dynamic HTML (DHTML) applications
Active X documents
Legacy one-tier Microsoft Access database with DAO or Remote Data Objects (RDO) data binding
Dynamic Data Exchange (DDE)
Object Linking and Embedding (OLE)
Once the Visual Basic 6.0 application has been classified as simple, medium, or advanced, efforts and schedules can be planned for migrating the application. Once the decision to migrate the application is made, the premigration changes are performed in the Visual Basic 6.0 application.