Postman Clone

Problem / Context

As a web-focused developer, I wanted to explore WinForms desktop development and deepen my understanding of how HTTP clients work under the hood. Building a simplified Postman-style tool was a practical way to combine both: building a desktop UI and understanding the workflow behind API testing tools. This project was inspired by a tutorial and built as a learning exercise.

Solution / Architecture

The application is a WinForms desktop app built in C# / .NET 10. It provides a UI for selecting the HTTP method (GET, POST, PUT, DELETE), entering a URL, optionally providing a request body, and viewing the formatted JSON response. HttpClient handles the actual HTTP communication. The focus was on understanding desktop UI patterns, event-driven WinForms programming, and correct use of HttpClient for API calls.

Goals

• Explore WinForms desktop development as a contrast to web-based UIs
• Understand how HttpClient works for making HTTP requests in C#
• Build a functional tool for sending HTTP requests and viewing responses
• Practice event-driven desktop UI programming

Challenges

• Learning WinForms layout and event model coming from a web background
• Handling async HTTP calls correctly in a WinForms event-driven context
• Displaying and formatting JSON responses in a readable way

Key Technical Decisions

• WinForms for a lightweight desktop UI without needing WPF or MAUI overhead
• HttpClient for HTTP communication – the standard .NET approach
• Kept scope intentionally small – the value is the learning, not a production tool

Results / Impact

• A working desktop tool for sending HTTP requests and viewing JSON responses
• Hands-on experience with WinForms, desktop event handling, and HttpClient
• Better understanding of how API testing tools work under the hood

What I Would Improve Next

• Add request history and saved collections
• Support custom headers and authentication flows
• Explore migrating the UI to .NET MAUI for cross-platform support