Component‑Based UI (Angular / React)
After understanding why WebForms cannot be migrated 1:1, the next step is adopting Component‑Based UI architecture.
This is the foundation of all modern frontend systems.
Modern UI is not page‑based — it is component‑based.
What Is a Component‑Based UI?
A component is a self‑contained UI block that includes:
HTML (Structure)
CSS (Style)
Logic (Behavior)
State (Data handling)
Examples:
Login Form
Navigation Bar
Data Grid
Profile Card
Dashboard Widget
Each component can be reused, tested, and maintained independently.
Why Component Architecture Matters
Legacy UI problems:
Duplicate code
Hard maintenance
Inconsistent design
Slow feature development
UI tightly coupled with backend
Component architecture solves this by enabling:
Reusability
Consistency
Faster development
Easier debugging
Team parallel work
Angular vs React (Quick Perspective) Angular
Full framework
Strong structure & conventions
Ideal for large enterprise apps
Built‑in routing, forms, DI
React
Library, highly flexible
Faster learning curve
Huge ecosystem
Great for dynamic UIs
There is no “better” — only better fit for team & project scale.
Key Concepts in Component UI
1. Reusability
Build once → Use everywhere.
Example: A button component used across the entire app.
2. State Management
Controls how data changes inside UI.
Tools: Redux, NgRx, Zustand, Context API.
3. Props / Inputs
Allow parent components to pass data to child components.
4. Event Handling
Child components communicate actions back to parents.
Migration Strategy from Legacy UI
Break Screens into Blocks
Instead of “Customer Page,” think:Header
Sidebar
Customer List
Detail Panel
Start With Shared Components
Buttons, forms, modals, grids — highest ROI.Adopt Design System Early
Typography, spacing, color themes, icons.Connect Only Through APIs
Never direct DB calls from frontend.
Common Mistakes
Building huge “mega components”
Mixing business logic in UI
Ignoring performance optimization
No naming conventions
No design consistency
Over‑engineering state management
Performance Best Practices
Lazy loading modules
Memoization / Pure components
Virtual scrolling for large lists
Code splitting
Image optimization
Success Indicators
You know component architecture is working when:
UI changes are localized
Code reuse increases
Feature delivery speeds up
Bugs reduce across screens
Design consistency improves
Teams work in parallel without conflict
Final Thought
Component‑based UI transforms frontend from page building to system building.
It creates a scalable, maintainable, and future‑ready interface layer that evolves smoothly with backend APIs.
You are no longer designing pages —
you are designing building blocks of experience.