Learn how to properly use null in C# in a modern way and write better, robust code
Null is often called the billion-dollar mistake, and for good reason. It can be very problematic. The idea of something having a nothing value sounds dangerous in software engineering. Over the years, C# has introduced features such as Nullable Reference Types to help developers write better, more robust, and safe code, but many people still don't know how to use it properly. In this course, Ed Charbeneau will start with the basics and teach you everything there is to know about null, from how to use it, from when not to use and how to take an existing full stack application that isn't using it properly and re-engineer it to make full use of the feature.
Curriculum
Welcome (00:45)
Who is the course for and prerequisites (00:43)
What will you learn in this course? (02:05)
Why is null important in C#? (01:43)
Why is null a problem in C#? (04:24)
The C# type system and value types (04:10)
Reference types in C# (03:14)
Unpacking the default keyword (03:52)
How C# uses types on the heap and stack (05:20)
A brief history of null in C# (00:52)
Nullable value types in C# 2+ (11:13)
Nullable reference types in C# 8+ (05:44)
Setting the nullable context (03:24)
Understanding common null compiler warnings (11:34)
Null intent is for compilers and developers too (09:33)
What is the null conditional operator? (06:26)
Using the null conditional operator with arrays (07:02)
What is null conditional short-circuiting? (03:05)
What is the null coalescing operator? (06:10)
What is the null coalescing conditional operator? (06:01)
What is the null forgiving operator? (06:30)
API design with null intent introduction (01:16)
Working with null and properties (05:01)
Unpacking the "Exiting the constructor" null warning (05:37)
What is the required keyword, and when to use it (05:19)
Advanced API intent with the AllowNull attribute (03:30)
Advanced API intent with the DisallowNull attribute (06:54)
Advanced API intent with the MemberNotNull attribute (04:58)
Advanced API intent with the NotNullIfNotNull attribute (03:18)
Introduction to pattern matching and the `is` keyword (06:04)
Property matching to filter null (10:40)
Capturing null with the pattern matching switch operator (05:16)
The BlazingPizza project overview (01:45)
Enabling the nullable context and treating warnings as errors (04:27)
How null affects EF migrations (07:43)
How null affects EF relationships (07:25)
Using the Visual Studio references feature to find null intent (06:34)
How null affects full-stack objects (04:02)
When to use the required keyword (05:46)
Updating shared classes with proper null intent (09:59)
Shared library walkthrough wrap up (06:10)
Web API best practices, GET operations (03:50)
Web API best practices, PUT operations (04:20)
Web API best practices, POST operations (02:05)
Web API best practices, DELETE operations (00:58)
Sample project only (no start and finish for this one) (05:36)
How to handle null with authorization and claims (02:46)
Improving an API with the DisallowNull attribute (03:09)
Fixing null issues with null operators (02:00)
Handling RazorComponents Authorization values (05:31)
How to handle Null with HttpClient (03:07)
Updating the application state object (02:58)
Applying null to Blazor pages (08:10)
Best practices for loading without relying on null in Blazor (02:27)
Unpacking the AuthenticationState component (06:23)
When to use EditorRequired in a RazorComponent (08:34)
Course Info
Level:
From Zero to Hero
Duration:
4h 38m
Rating (New):
Lifetime access
Add to CartAbout the Author
Ed Charbeneau
Ed is a Microsoft MVP and an international speaker, writer, online influencer, a Developer Advocate for Progress, and expert on all things web development. Ed enjoys geeking out to cool new tech, brainstorming about future technology, and admiring great design.
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