81
What are extension methods in C#?
Extension methods allow developers to add method-like functionality to an existing type without modifying that type or creating a derived class.
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Advanced C# Language Features
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82
What is pattern matching in C#?
Pattern matching allows code to test an object's type, value, shape, or properties and optionally extract information at the same time.
83
What is a switch expression in C#?
A switch expression is a concise expression-based form of switch that returns a value based on pattern matching.
84
What is the null-coalescing operator (??) in C#?
The null-coalescing operator returns its left operand when that value is not null; otherwise, it evaluates and returns the right operand.
85
What are the null-conditional operators ?. and ?[] in C#?
Null-conditional operators safely access a member or index only when the target object is not null.
86
What are ref, out, and in parameters in C#?
ref, out, and in pass arguments by reference rather than passing the parameter value normally.
87
What are tuples in C#?
Tuples allow a method or expression to group multiple values without defining a separate class or struct for every temporary result.
88
What is the yield keyword in C#?
The yield keyword is used to implement an iterator without manually building and returning the entire collection.
89
What is reflection in C#?
Reflection allows code to inspect metadata about assemblies, types, properties, methods, attributes, constructors, and other members at runtime.
90
What are attributes in C#?
Attributes attach declarative metadata to assemblies, classes, methods, properties, parameters, and other program elements.