The 7 Structural Design Patterns with:
Definition
Problem Statement
UML Diagram
Real-world Example
Complete C# Console Application
ASP.NET Core Example
Advantages
Disadvantages
Best Practices
Common Mistakes
Interview Questions
Part 3.1 – Adapter Design Pattern
You'll learn:
What is the Adapter Pattern?
Why incompatible interfaces become a problem
Object Adapter vs Class Adapter
Adapter Pattern Structure
UML Class Diagram
Real-world Examples (Power Adapter, USB Adapter)
Complete C# Console Application
ASP.NET Core Example
Advantages and Disadvantages
Best Practices
Common Mistakes
Interview Questions
Part 3.2 – Bridge Design Pattern
Topics:
What is the Bridge Pattern?
Abstraction vs Implementation
Composition over Inheritance
UML Diagram
Complete C# Example
ASP.NET Core Example
Real-world Examples
Advantages
Disadvantages
Interview Questions
Part 3.3 – Composite Design Pattern
Topics:
Tree Structures
Parent–Child Relationships
Composite vs Leaf Objects
UML Diagram
File System Example
Organization Hierarchy Example
C# Console Application
ASP.NET Core Example
Advantages
Disadvantages
Interview Questions
Part 3.4 – Decorator Design Pattern
Topics:
Dynamic Behavior Addition
Wrapper Objects
Decorator vs Inheritance
Coffee Shop Example
Middleware Analogy in ASP.NET Core
Complete C# Example
UML Diagram
Advantages
Disadvantages
Best Practices
Interview Questions
Part 3.5 – Facade Design Pattern
Topics:
Simplifying Complex Systems
Wrapper APIs
Banking System Example
Home Theater Example
ASP.NET Core Integration
UML Diagram
C# Console Example
Advantages
Disadvantages
Interview Questions
Part 3.6 – Flyweight Design Pattern
Topics:
Memory Optimization
Shared Objects
Intrinsic vs Extrinsic State
Text Editor Example
Game Development Example
UML Diagram
Complete C# Example
ASP.NET Core Example
Advantages
Disadvantages
Performance Considerations
Interview Questions
Part 3.7 – Proxy Design Pattern
Topics:
Virtual Proxy
Remote Proxy
Protection Proxy
Smart Proxy
Lazy Loading
Entity Framework Core Proxy
C# Example
ASP.NET Core Example
UML Diagram
Advantages
Disadvantages
Interview Questions
What You'll Learn in Part 3
By the end of the Structural Design Patterns section, you'll understand:
How to connect incompatible interfaces using Adapter.
How to separate abstraction from implementation with Bridge.
How to represent hierarchical tree structures using Composite.
How to add functionality dynamically using Decorator.
How to simplify complex subsystems with Facade.
How to optimize memory usage using Flyweight.
How to control access to objects using Proxy.
You'll also see how these patterns are applied in modern C# and ASP.NET Core applications, including Dependency Injection, middleware pipelines, Entity Framework Core, cloud integrations, and enterprise architectures.
Next Article
We'll begin Part 3.1 – Adapter Design Pattern, covering:
What is the Adapter Pattern?
Why incompatible interfaces become a problem
Object Adapter vs. Class Adapter
UML Class Diagram
Complete C# Console Application
ASP.NET Core implementation
Real-world examples
Advantages and disadvantages
Best practices
Common mistakes
Interview questions
The Adapter Pattern is one of the most practical structural patterns and is widely used when integrating third-party libraries, legacy systems, external APIs, or services with incompatible interfaces. It provides a clean way to make otherwise incompatible components work together without modifying their existing code.
