Post-migration Changes Overview
As seen in the previous section, once a Visual Basic 6.0 application is opened in Visual Studio .NET, the upgrade wizard is invoked to facilitate the upgrade to Visual Basic .NET. On running the upgrade wizard, an upgrade report is produced that lists all the issues faced and the problem areas identified during the upgrade process.
Based on the upgrade report findings and the desired functionality in Visual Basic .NET, the developer needs to change the code in Visual Basic .NET. The objective of this phase is to write code in Visual Basic .NET to obtain the same functionality in the migrated code. To simplify the post-migration changes, the changes have been categorized by the commonly used features and functionality in Visual Basic 6.0. A few of the features are as follows:
Help functionality
Database operations
Windows API calls
Drag and drop functionality
Menus
MDI forms
The post-migration recommendations are covered in detail in Chapter 4.
Pre-migration Recommendations
Visual Basic .NET is radically different from Visual Basic 6.0. To convert Visual Basic 6.0 applications into Visual Basic .NET, developers need to learn the features of the .NET Framework. This section covers the changes between Visual Basic 6.0 and Visual Basic .NET languages.
Microsoft has also provided some recommendations on the changes to be made to an existing Visual Basic 6.0 application so that the upgrade to Visual Basic .NET is as smooth as possible. The next section covers the language and syntax changes as well as the pre-migration recommendations given by Microsoft.