ChatGPT for VB6 to C# migration

Abto Software
4 min readJan 31, 2024

This post is a quick overview of an Abto Software blog article.

ChatGPT capabilities to facilitate VB6 to C# migration

ChatGPT is being utilized across different industry verticals to automate and optimize everyday processes. These include data analysis and reporting, language translation and localization, and even customer support, among many other things.

Under supervision, ChatGPT can be used to simplify VB6 migration by handling:

  • Code analysis
  • Pseudo-code generation
  • Code translation
  • Code troubleshooting

ChatGPT might provide assistance at all project stages, from initial project planning to execution and support. The algorithm can complement existing knowledge and experience, fostering productivity and efficiency, eventually minimizing project delays.

Before leveraging ChatGPT capabilities to optimize VB6 migration, it’s essential to consider:

  • Project requirements
  • Determined budget and timeline
  • The complexity of the legacy codebase
  • Available expertise and resources
  • Data migration and integrity
  • System integration and compatibility
  • Risk assessment
  • Alternative approaches
  • Regulatory compliance
  • Post-migration support

ChatGPT application from investigation to continuous post-migration support

Initial discovery

  • Requirement gathering — ChatGPT helps to collect and clarify business requirements by generating relevant questions about the prospective project
  • Code understanding — ChatGPT helps to review and interpret the legacy code inspected, its structure, its dependencies, and other critical components to ensure positive outcomes

Project planning

  • Strategy creation — the bot provides recommendations on the best-suiting approach for converting specific components and modules to the target technology, which helps software developers migrate VB6 to C# sensibly faster
  • Stack selection — the bot gives suggestions on the best-fitting technology by reviewing and analyzing the requirements previously gathered, which allows software engineers migrate VB to C# much easier

Code analysis

  • Construct explanation — ChatGPT can be efficiently used to clarify the purpose and behavior of specific code constructs, helping developers find equivalents in the target technology
  • Pseudo-code generation — ChatGPT can also be used to generate high-level representations of complex code parts, empowering engineers feeling overwhelmed with the legacy codebase

Testing and quality assurance

  • Test generation — the chatbot can help to generate test cases to ensure positive outcomes
  • Code debugging — the assistant can help to find efficient solutions to resolve discovered problems

Code refactoring and optimization

In addition, ChatGPT can provide recommendations on how to optimize software stability and maintainability.

Deployment and post-migration support

What’s more, ChatGPT helps to address technical challenges by providing detailed guidance on optimization after migration.

ChatGPT assistance during migration, the benefits

Utilized wisely, not to replace humans, but to automate processes, ChatGPT can bring great business value:

  • Reduced costs — by improving smaller processes and minimizing potential inconsistencies, the chatbot provides control over the project’s budget
  • Reduced time — by enhancing code translation and troubleshooting among other important processes, the chatbot sensibly minimizes development timelines, naturally allowing business leaders to harness the benefits of modernization much sooner
  • Better documentation — the program can help generate documentation, ensuring straightforward application maintenance and updates
  • Simplified maintenance — the assistant can provide detailed documentation and suggestions to deliver better code being easier to maintain and extend

ChatGPT assistance during migration, main challenges

Here are the most common challenges that arise due to fundamental differences between the two languages:

  • Data types — VB6’s Variant data type doesn’t have a direct C# equivalent, and might require replacement with Object, or better, code refactoring
  • Array boundaries — VB6 arrays are by default 0-based, but can be changed to 1-based using the Option Base 1 declaration, C# arrays are 0-based, which can potentially cause off-by-one errors
  • Error handling — talking about error handling, VB6 is using the On Error Goto mechanism, C# is using the try-catch-finally structure, which means VB6 conversion can be quite tricky
  • Event handling — talking about event handling, VB6 uses event interfaces, C# uses both delegates and events, which means significant transformation during migration
  • Late binding — VB6 allows late binding using Variant or CreateObject, while target C# prefers early binding
  • Default properties — VB6 allows its objects to have default properties, which are called automatically, while target C# does not support default properties, so code that relies on them requires refactoring
  • Parameter passing — VB6 parameters (value and reference types) are passed by reference by default, while, on the contrary, C# parameters are passed by value unless explicitly marked with ref or out keyword
  • UI components — VB6’s components and the entire form design approach is significantly different from C#’s WinForms, and other UI frameworks

Summing up

Abto Software is there to empower business leaders who approach VB6 to C# migration for modernization. From initial project discovery to planning, code conversion, deployment, optimization, as well as maintenance, our company can handle every stage to let the decision-makers fully focus on their core goals.

Contact us for smooth VB6 to C# migration and enjoy greater performance right away!

We handle:

  • Business analysis and consulting
  • Project setup and kick-off
  • Code migration
  • Code finalization
  • Acceptance testing and improvement
  • Quality assurance and deployment

To deliver:

  • Reduced time and cost
  • Increased performance
  • Optimized security
  • Better compatibility, flexibility, scalability, and integration



Abto Software

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