C# Fundamentals

Question 1 Report

Senior: What is the purpose of nullable reference annotations?

Think compiler analysis.

Convert references into Nullable Guarantee no NullReferenceException Communicate nullability intent and enable warnings Validate databases automatically

Question 2 Report

Senior: Why are readonly fields useful?

Think reassignment after construction.

They are identical to const They restrict reassignment after initialization They can only be assigned at compile time They make referenced objects deeply immutable

Question 3 Report

Architect: Why are namespaces not security or deployment boundaries?

They organize names.

Each namespace is a process Namespaces encrypt types They organize type names but do not create process, assembly, or security isolation Namespaces replace access modifiers

Question 4 Report

Fresher: Which loop commonly has initializer, condition, and iterator sections?

Classic counter-controlled loop.

for namespace using catch

Question 5 Report

Senior: What does params allow?

Variable argument count.

Zero or more arguments for the final parameter Every parameter becomes optional All args become strings The method becomes generic

Question 6 Report

Fresher: Which declaration correctly stores a single character?

Single characters use single quotes.

char grade = "A"; bool grade = 'A'; string grade = 'A'; char grade = 'A';

Question 7 Report

Fresher: What does continue do in a loop?

The loop continues.

Exits the method Terminates the loop Skips the rest of the current iteration and continues Repeats without normal loop mechanics

Question 8 Report

Senior: What is the purpose of finally?

Cleanup when leaving a try region.

Run cleanup-oriented code whether the try succeeds or an exception propagates Guarantee process survival Declare constants Catch only null errors

Question 9 Report

Senior: What is the intent of an in parameter?

Readonly by-reference input.

Convert the method to a constructor Allow free replacement Force heap allocation Pass by reference while preventing reassignment inside the method

Question 10 Report

Fresher: What does % return for integer operands?

Think about division remainder.

A Boolean The rounded quotient A percentage The remainder

Question 11 Report

Senior: What does ref allow a method to do?

The parameter aliases the caller's variable.

Make it permanently readonly Read and assign the caller's variable Convert it to object Guarantee thread safety

Question 12 Report

Senior: Why is catching a specific exception type useful?

Different failures need different handling.

It prevents the failure from occurring Exception can never be caught Specific exceptions always run faster It allows precise handling of a known failure

Question 13 Report

Architect: Why is choosing class versus struct a semantic API decision, not just a memory optimization?

Think value versus reference semantics.

It changes copying, identity, and value/reference behavior exposed to callers They have identical semantics Structs are always faster Classes cannot contain methods

Question 14 Report

Fresher: What do top-level statements allow in modern C#?

Think about small console apps.

Multiple Main methods executing together Running C# without compilation Classes without names Executable statements without explicitly declaring Main

Question 15 Report

Senior: Why can condition1 && condition2 skip condition2?

The result may already be known.

&& evaluates only one operand always Evaluation order is random condition2 is compiled out && short-circuits when condition1 is false