VB.NET WinForms Patch Development

@Microlent

Hello, I am Dr. Rajesh Rolen, PhD in Computer Science & Engineering, with experience of over 20+ years in API Integration, Software Development, Web Services, SQL, .NET, Microsoft SQL Server, Software Engineering As a preferred freelancer in the top 1%, I have done 400+ projects here on freelancer.com, I have 4.9 ratings out of 5 on average, which showcases my quality of work and timely delivery. Key Highlights: - Free Hosting Support on the Cloud or any desired platform. - Free 3 months of post-delivery support to ensure that our client doesn’t face any challenges after the launch of the project. - Free Dedicated tester on projects to ensure quality delivery, so clients don’t need to act as a tester. - 10+ Years experience UI/UX team to ensure intuitive UI. Portfolio: https://www.freelancer.com/u/Microlent Please open the chat and send me a message, so we can have a more detailed discussion about the project to give you the project timeline and cost. Thank you for considering my services. I look forward to engaging in a productive conversation and understanding how I can be of assistance in bringing your project to life. Regards Rajesh Rolen

@customizedata

Please provide some details about the existing VB.net based application to clarify the scope of work 1-Which .Net framework version existing legacy code base is using ? 2-Does the existing legacy app use some layered coding pattern or direct code behind approach is being used ? 3-Please mention which APIs and WebServices are required to be integrated .. Do they use oAuth base mechanism or some token based authentication ? Have been developing .Net based applications since 2010 .. Already integrated countless APIs /SDKs e.g. Quickbooks, Xero , Financial apis , Hardware based integrations etc Looking forward to have a chat with you to discuss further.

@motysaqa

Hi, The VB code is already written and tested, so the real job isn't writing code. It's the three things that break when a direct SQL call becomes an HTTP call inside WinForms. UI thread. SQL returned in milliseconds; an HTTP call takes hundreds, or hangs. If that Sub runs in a loop the form looks frozen and users start clicking twice. Wrapping the async call in .Result to fit the old signature deadlocks under load. Transactions. If the old Sub ran inside a transaction, an API call can't join it. API succeeds, local commit fails, and there's a record in the new ERP and nothing on your side. Needs an idempotency key and a decision up front: retry, or compensate. TLS. On an older .NET Framework, TLS 1.2 isn't on by default. Works on the dev machine, fails on site. One line to fix, a long afternoon to find. How I'd work it: read the Sub, find every call site including anything relying on a side effect (a returned ID, a log row it also wrote). Then wire your Sub in behind a config switch, so the person on site can flip back to the old path instantly if something looks wrong. Then test with them live. VB.NET, C#, SQL Server and Windows are my daily stack, so legacy Windows apps are home ground rather than a stretch. I'd want to read the Sub before quoting firmly; rough guess 20h. Two questions meanwhile: which .NET Framework version, and is that Sub called inside a loop or a transaction? Motasem Alsaqqa

@MashoodurRehman1

I am an experienced VB.NET developer with a strong background in WinForms applications, specializing in seamlessly integrating APIs and web services. My expertise extends to handling legacy codebases, ensuring new features are effectively integrated without disrupting system stability or performance. In previous projects, I have successfully navigated the complexities of legacy systems, implementing modern solutions to replace outdated functionalities. I am adept at troubleshooting and efficiently resolving integration issues, leveraging my proficiency in SQL and ERP systems. I understand the importance of maintaining a stable environment during transitions and can ensure a smooth API integration process as required by your project. I am keen to discuss how my skills align with your needs and am available to provide further information. Could you please share the testing parameters you wish to emphasize during the performance assessment? This will help ensure alignment with onsite testing objectives.

@Hrolgar

The trade-off is whether to touch the surrounding form logic at all or leave it alone and only swap the data source. Your Sub is already drafted and tested against the new API, so the safest path is treating it as a drop-in replacement for the old SQL call and changing as little else as possible, but legacy WinForms code has a habit of depending on side effects the original Sub had, timing of when fields populate, error handling that the rest of the form silently relies on, so a truly clean swap only works if none of that got baked in. I'd start by tracing every call site of the current Sub and everything downstream that reads its output, then map that against what your new Sub actually returns before wiring anything in. That's the part worth getting right before writing a line, since guessing wrong here means redoing the integration rather than just the Sub itself. Once that's mapped the wiring is straightforward, and the actual validation is where the remote session with your tester earns its keep, since performance on a live ERP call can behave differently than it did in isolation. M1: Investigate legacy code, map Sub call sites and dependent logic, 210 EUR, 2d. M2: Wire in the new Sub and adapt surrounding code, 260 EUR, 2d. M3: Live validation session with your tester, fix issues found, 170 EUR, 1d.

@usmanbashir12100

Hi, I can work directly within the existing VB.NET WinForms codebase to trace the legacy Sub, understand its current SQL/ERP dependencies, and replace the relevant flow with your already tested new ERP API integration. I’ll adapt the proposed Sub where necessary, preserve existing application behavior, handle API errors and data mapping carefully, and coordinate with your on-site person for functional and performance testing. A few questions: * Can you provide the current Sub and the draft replacement Sub for an initial code-level review? * What API protocol and authentication method does the new ERP use? * Are there existing test cases or expected input/output results for the old ERP operation? Best regards, Muhammad Usman

@AbdulBasitAli045

Dear Client. When it comes to your project, i am expert. I will provide you 100% satisfaction work and full service. It would be great if you hire me. Based on your feedback, I can draft my proposal accurately and from there I can get started. Hence, I look forward to hear back from you in order to proceed ahead accordingly. Let's Go Thanks a lot. Regards

@prprojectsl

Hi, This looks like a contained but careful legacy integration: understand what the current SQL-based Sub does, preserve its surrounding WinForms behavior, and replace the ERP boundary without destabilizing the application. I would first trace the Sub's callers, inputs, outputs, database side effects, error handling, and any UI-thread dependencies. I would then compare those expectations with the tested API code and draft replacement, adapt the mapping, authentication, and configuration where needed, and integrate it with explicit timeout and failure handling. Testing with the onsite contact should cover normal transactions, API errors, incomplete data, response time, and confirmation that the old ERP dependency is no longer used in that path. My background includes APIs, databases, integrations, troubleshooting, and application development. I also have academic familiarity with Visual Basic and C#, so I can approach the VB.NET code honestly without overstating specialization. Before finalizing scope, I would like to review the relevant code, API documentation, access method, and test/rollback process. I can help turn the existing draft into a stable, testable patch while coordinating closely with the person onsite. Regards, Priyam

@netcoder

Hi, I have experience in working with VB.NET and older applications because I have long-time experience. :-) I also worked with old Visual Basic 6 in the past.

@ZohaibRoy

⭐⭐⭐⭐⭐ Enhance Your VB.NET WinForms App with API Integration ❇️ Hi My Friend, I hope you're doing well. I just reviewed your project requirements and see you are looking for a developer to add new features to your VB.NET WinForms application. You don’t need to look any further; Zohaib is here to help you! My team has completed over 50 similar projects for VB.NET applications. I will carefully examine the legacy code to ensure a smooth integration with the new APIs and web services, maintaining stability and performance throughout the process. ➡️ Why Me? I can easily enhance your VB.NET WinForms application as I have 5 years of experience in VB.NET development, API integration, and working with legacy code. My skills include troubleshooting, performance testing, and ensuring seamless data exchange. Additionally, I have a strong grip on debugging and optimizing applications to meet your needs effectively. ➡️ Let's have a quick chat to discuss your project in detail and let me show you samples of my previous work. I look forward to discussing this with you in our chat. ➡️ Skills & Experience: ✅ VB.NET Development ✅ WinForms Application ✅ API Integration ✅ Legacy Code Analysis ✅ SQL Server Management ✅ Performance Testing ✅ Debugging Skills ✅ Data Exchange Techniques ✅ Application Optimization ✅ Troubleshooting ✅ Web Services Integration ✅ User Interface Design Waiting for your response! Best Regards, Zohaib

@starttechno

Replacing the legacy SQL-to-old-ERP Sub with the tested new ERP API call is a focused VB.NET WinForms integration task, and I can work directly within the existing code rather than rewriting unrelated areas. I will first trace the current Sub, its callers, parameters, SQL mappings, transaction flow, and UI dependencies. I will then review the proposed API-based Sub, adapt it to the existing data structures and error-handling conventions, and preserve the expected return values and application behavior. I’ll also check authentication, request/response mapping, timeouts, retries, logging, and exception handling so an ERP/API issue cannot destabilize the WinForms application. Where appropriate, I’ll ensure the call does not unnecessarily block the interface. After integration, I’ll test the complete path against representative data, compare the old and new results, and work with the person on site to verify performance and edge cases. I’ll keep the change isolated and provide a clear summary of what was modified. I previously resolved a live trading platform’s frozen charts caused by an unthrottled external API by adding caching, usage controls, and last-good-value handling—useful experience for keeping integrations stable. Is the tested new ERP Sub draft already in the same VB.NET solution as the legacy Sub? Muhammad Saad

@denisSolution

Hi, I'm Denis and I've worked on VB.NET WinForms applications that needed modern integrations with external systems. You're looking to replace an existing SQL-based ERP integration in your legacy code with a new API-based approach, and the new API integration is already prepared. I'll start by reviewing the current Sub that handles the old ERP connection to understand how it's used in the application flow. Then I'll integrate the new API call while maintaining the same input/output behavior so the rest of the system remains unaffected. Since the new Sub is already tested, the focus will be on making sure it works smoothly within your application context. The main risk here is the legacy code's assumptions about the old integration—for example, transaction handling or error scenarios might differ between the SQL and API approaches. I'll make sure to preserve those behaviors while switching to the new method. I can start working right away. Let's connect and discuss the details. Thanks, Denis.

@ykarora26

With a deep understanding of VB.NET and WinForms, I am well-equipped to seamlessly integrate various APIs and web services into your existing application. My experience in troubleshooting and enhancing legacy code makes me the ideal candidate for this project. Could you provide more details about the specific APIs and web services that need to be integrated to ensure a smooth data exchange process? Regards, Yogesh Kumar

@AndrewJSMAN

I’ve replaced legacy ERP SQL calls with REST API integrations in VB.NET WinForms before, so this is right in my wheelhouse. I’ll pull the existing Sub, map its data flow to the new API payload, and swap the SQL logic with the drafted call—validating request/response schemas against the old SQL output first. After local smoke tests, I’ll run parallel tests with the on-site user to catch latency or schema mismatches, then push the patched module with rollback script if needed. I can start immediately. Thanks, Andrii.

@jayantkumar314

Hi, I can review the existing VB.NET WinForms legacy code and safely replace the old ERP SQL workflow with your already-tested new ERP API implementation. I’ll integrate/adjust the drafted Sub while preserving the existing application behavior and error handling. I can also troubleshoot the integration and work with your on-site contact during functional and performance testing. I’m ready to start with a review of the existing Sub and the new API implementation.

@augustogus

Hi, I read the full description, including the part at the end about the Sub, so let me play it back to you: right now it builds SQL against the old ERP, you already have working VB code for the new ERP API, and there's a draft replacement Sub. What's left is getting that draft properly wired into the WinForms app and proving it behaves the same as before. That's most of what I do. Old desktop applications where the business logic is fine but the data layer has to point somewhere new. In my experience the API call is never the hard part. The hard part is finding what else in the app depends on that Sub's output or its side effects. One thing before I lock a number: can you send me the current Sub and your draft? A screenshot is fine. If it's self-contained this is quick. If it's called from several places or writes to shared state, better we both know now. My bid assumes the integration plus two testing sessions with your on-site person, booked in advance so neither of us is left waiting.

@KarthikTechCon

Senior VB.NET/WinForms Developer: With 15+ years of experience, I specialize in enhancing legacy applications. I will seamlessly integrate your VB.NET WinForms application with the required APIs, ensuring optimal performance and stability. Execution Strategy: - Analyze existing legacy code to identify integration points for the new ERP API. - Implement the new Sub to replace the existing SQL connections, ensuring data consistency. - Collaborate with on-site personnel for real-time testing and troubleshooting. Scope of Delivery: - Integrated functionality for seamless data exchange with the new ERP. - Thorough documentation of modifications for future reference. - Performance assessment to ensure system reliability post-integration. Quality & Performance: - Maintain application stability throughout the integration process. - Conduct rigorous testing to ensure all new features perform as expected. Timeline & Next Steps: - Initial investigation and integration within 2-3 weeks, followed by testing and adjustments based on feedback. - I am available for ongoing support and updates as required. Best Regards, Karthik B Resonite Tech

@SkillCrafts

I understand you need a VB.NET developer to integrate your WinForms application with external APIs and web services, similar to projects where I've successfully connected legacy systems to modern cloud platforms, ensuring robust data flow and minimal disruption. My approach will involve thoroughly analyzing your existing codebase to identify optimal integration points. I'll leverage established .NET libraries for API communication (e.g., `HttpClient` for RESTful services, `SoapHttpClientProtocol` for SOAP) and implement robust error handling and retry mechanisms. A phased development plan will ensure each integration is tested independently before full deployment, maintaining application stability and performance. Could you share the specific APIs you intend to integrate with, and are there any particular security protocols that need to be adhered to? I'm available for a brief call to discuss your project in more detail.

@demivision

Hi there, Thank you for outlining your requirements in such detail. I understand you need to enhance your existing VB.NET WinForms application by replacing a legacy SQL-based Sub with a new API-driven integration to your ERP system. Your emphasis on maintaining application stability throughout the patching process, especially when dealing with legacy code, is well noted. I have extensive experience working with VB.NET, WinForms, and both legacy and modern ERP integrations. My background includes numerous projects where I have successfully implemented API and web service integrations, often within mature codebases. This has equipped me with a strong ability to analyze, refactor, and extend existing code while ensuring stability and high performance. For your project, my approach would be to first thoroughly investigate the current Sub and its interactions within the application. I will carefully review the new draft Sub and the tested ERP API code to ensure they align with your application’s structure and standards. Integration will be done incrementally, with rigorous testing at each step. I am comfortable collaborating with your on-site contact to verify functionality and performance, and I will ensure that any issues are quickly identified and resolved. I am committed to delivering a robust solution that seamlessly connects your application with the new ERP, while preserving the reliability your users expect. I look forward to discussing the project further and understanding any specific testing or deployment requirements you may have. Best regards, DemiVision, LLC