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Mastering NullReferenceException Prevention in C#

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NullReferenceException is an error that programmers frequently encounter, and it is often referred to as the Billion Dollar Mistake. This course is designed to assist you in avoiding this error. You will begin by gaining an understanding of when NullReferenceException is thrown and how to prevent null in your code. You’ll also learn how to employ nullable operators to simplify null checks and use nullable references and the Option wrapper to identify problematic code blocks. Finally, you will explore avoiding NullReferenceException when using specific LINQ methods and designing your C# classes. Upon completing this course, you’ll have gained the necessary knowledge and skills to effectively address and avoid NullReferenceException issues in your projects.

NullReferenceException is an error that programmers frequently encounter, and it is often referred to as the Billion Dollar Mist...Show More

WHAT YOU'LL LEARN

An understanding of NullReferenceException and when it can be thrown

A working knowledge of C# nullable operators to simplify null checks

The ability to identify problematic code blocks using C# nullable references

Familiarity with the Option wrapper to avoid NullReferenceException

The ability to avoid NullReferenceException when working with some LINQ methods

An understanding of NullReferenceException and when it can be thrown

Content

18 Lessons2 Quizzes

Strategies to Get Rid of NullReferenceException

18 Lessons

About This Course

What Is the NullReferenceException?

Exercise: NullReferenceException and Collections

Quiz on NullReferenceException

Checking and Preventing Null

Exercise: Refactoring a Function to Prevent Null

C# 6.0-8.0 Nullable Operators

Quiz on Nullable Operators

C# 8.0 Nullable References

Exercise: Fixing Compilation Errors with Nullable References

Use the Option Wrapper

Exercise: Practicing Utility Methods from the Optional Library

Implement Your Option Wrapper

LINQ XOrDefault Methods

Exercise: LINQ XOrDefault Methods

Separate Objects and Separate State

Exercise: Solve a Real NullReferenceException Issue

Wrap Up!

Certificate of Completion

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Course Author:

Cesar Aguirre

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