.NET Web Development, Week 9

Meeting Purpose

Introduce and implement stack data structures using arrays and linked lists in JavaScript.

Key Takeaways

• Stacks are Last-In-First-Out (LIFO) data structures, implemented using arrays and linked lists
• Key operations push, pop, peek, and isEmpty all run in O(1) time
• Implemented both an ArrayStack and a ListStack backed by a custom StackNode class

Meeting Purpose

Introduce LINQ (Language Integrated Query) and practice its usage in C# for data manipulation and querying.

Key Takeaways

• LINQ provides SQL-like querying capabilities within C#, bridging data and code
• Covered method syntax for filtering (Where), sorting (OrderBy/ThenBy), and aggregation (Count/Sum/Max)
• Multiple LINQ methods can be chained together for complex data transformations

Meeting Purpose

Finish tasks left off from the morning session, focusing on LINQ queries and breaking into breakout rooms.

Key Takeaways

• FirstOrDefault() is preferred over First() to avoid exceptions when no results are found
• Projection with Select() is crucial for creating view models in MVC applications
• LINQ queries aren't executed until iterated over or ToList() is called

Meeting Purpose

Review and discuss solutions for four stack-based algorithms implemented during breakout sessions.

Key Takeaways

• Covered four algorithms using stacks: reverse string, is palindrome, valid parens, and next greater
• The next greater algorithm proved hard to implement with a stack, leading to an array-based O(N^2) solution
• Discussed a potential O(N) solution for next greater by traversing the array backwards

Meeting Purpose

Introduce and begin building a .NET Web API project for movie data.

Key Takeaways

• Created a new .NET Web API project and implemented GET endpoints for all movies and a movie by ID
• Reviewed RESTful principles: plural resource names, standard HTTP methods, and status codes
• Explored testing tools including Swagger UI, Thunder Client, and Postman

Meeting Purpose

Discuss and implement search functionality for a movie API using query strings and LINQ queries.

Key Takeaways

• Implemented a search endpoint with optional query parameters for keyword and minimum rating
• Used AsQueryable() to future-proof the API for EF Core integration
• Covered error handling and appropriate HTTP status codes for search results

Meeting Purpose

Review and implement queue-based data structures and algorithms, focusing on an ArrayQueue class and a Hot Potato elimination game.

Key Takeaways

• Queues are FIFO data structures, in contrast to LIFO stacks
• Implemented an ArrayQueue class with isEmpty, enqueue, dequeue, peek, and size
• The Hot Potato algorithm simulates a Josephus-style elimination game using a queue

Meeting Purpose

Implement mutative operations (create, update, delete) in a .NET Web API with an in-memory dataset.

Key Takeaways

• Converted the read-only dataset to mutable to support CRUD operations
• Implemented POST, PUT, and DELETE endpoints with appropriate status codes
• Resolved issues with in-memory data persistence across requests

Meeting Purpose

Continue work on API development, focusing on database integration and asynchronous operations.

Key Takeaways

• Transitioned from an in-memory API to a database-backed API using Entity Framework Core
• Introduced Inversion of Control and Dependency Injection concepts
• Created an initial migration and verified the database schema in MySQL Workbench

Meeting Purpose

Review and implement queue data structures using linked lists and discuss binary search tree traversal algorithms.

Key Takeaways

• Implemented a LinkedListQueue class, improving on ArrayQueue's dequeue efficiency (O(1) vs O(n))
• Explored level-order traversal (breadth-first search) for binary search trees using a queue
• Practiced test-driven development for both implementations

Meeting Purpose

Review and migrate movie API endpoints from an in-memory database to a persistent EF Core database, including refactoring to asynchronous operations.

Key Takeaways

• Migrated all CRUD operations from in-memory storage to a persistent MySQL database using EF Core
• Created async versions of all controller methods for improved scalability
• Added data validation with custom error messages to protect API endpoints