“Extension Methods” in Information Technology

13 questions across 2 technologies.

Information Technology

13 questions in 2 technologies

#	Question	Technology	Topic	Level
1	Why must extension methods be defined in a static class, and how does the compiler resolve a call to one? C# › Extension Methods	C#	Extension Methods	Beginner
2	How do you chain multiple extension methods together in a fluent style, and what design principle makes this possible? C# › Extension Methods	C#	Extension Methods	Intermediate
3	What are extension methods in C#, and how do they let you add functionality to a type you can't modify? C# › Extension Methods	C#	Extension Methods	Intermediate
4	How would you write extension methods to build a lightweight, fluent validation/guard-clause library? C# › Extension Methods	C#	Extension Methods	Advanced
5	Why can't extension methods be used to add STATIC members, operators, or FIELDS to an existing type, and what are the practical implications of this limitation? C# › Extension Methods	C#	Extension Methods	Advanced
6	How do 'extension method ambiguity' conflicts arise when two different NuGet packages or namespaces define extension methods with the identical signature, and how do you resolve them? C# › Extension Methods	C#	Extension Methods	Advanced
7	How would you write generic extension methods leveraging C# 11's generic math interfaces (like INumber<T>) to build a single reusable numeric utility working across int, double, decimal, and other numeric types? C# › Extension Methods	C#	Extension Methods	Advanced
8	What is an extension method, and what syntax makes a static method into one? C# › Extension Methods	C#	Extension Methods	Beginner
9	How does method resolution priority work when an extension method has the SAME name and signature as an actual instance method on the type? C# › Extension Methods	C#	Extension Methods	Intermediate
10	How do you write a generic extension method that works with any collection type, like a custom 'IsEmpty()' check? C# › Extension Methods	C#	Extension Methods	Intermediate
11	How would you write an extension method on an interface (like IEnumerable<T>) that provides a default implementation shared across EVERY concrete implementing type? C# › Extension Methods	C#	Extension Methods	Advanced
12	What are extension methods in Dart, and how do they let you add new useful functionality directly onto an existing class, including classes you did not originally write yourself, such as Dart's own built in String class? Flutter › Dart Language Basics & Syntax	Flutter	Dart Language Basics & Syntax	Intermediate
13	How would you write an extension method to safely add or remove a specific flag from a [Flags] enum value without manual bitwise operators scattered throughout your code? C# › Enums & Flags	C#	Enums & Flags	Advanced