Type conversion in C#.NET and VB-style helpers: which statement is correct? Consider these claims about conversions and literals: • Information is never lost during narrowing conversions. • The CInteger() helper can convert a Single to an Integer. • Widening conversions take place automatically. • Assigning an Integer to an Object variable is called unboxing. • The literal 3.14 can be treated as Decimal using the suffix F.

Difficulty: Easy

Correct Answer: Widening conversions take place automatically.

Explanation:


Introduction / Context:
Understanding numeric and object conversions in .NET avoids runtime errors and precision loss. This question distinguishes widening vs. narrowing conversions, boxing/unboxing, and literal suffixes.



Given Data / Assumptions:

  • C# provides implicit conversions for widening (safe) cases and requires explicit casts for narrowing (potentially lossy).
  • VB helper names (e.g., CInt) should not be confused or assumed available in C#.
  • Literal suffixes F and M/D refer to Single and Decimal respectively.


Concept / Approach:
Widening conversions are implicit (e.g., int to long, float to double) because they cannot overflow by definition within the type system's range rules. Narrowing conversions (e.g., double to float, long to int) are explicit and can lose information. Boxing is converting a value type to object; unboxing is the reverse. For decimal literals, the correct suffix is M (or m), not F.



Step-by-Step Solution:

Evaluate each statement for correctness.Narrowing conversions can lose information → statement about “never lost” is false.CInteger() is a VB helper; in C# use casts or Convert; the claim as stated is not applicable/correct.Widening conversions are implicit → true.Assigning int to object is boxing, not unboxing → false.3.14F denotes a Single, not Decimal → false (use 3.14M).


Verification / Alternative check:
Compile small samples: implicit int→long works; long→int requires a cast. Literal 3.14M compiles to Decimal; 3.14F is Single.



Why Other Options Are Wrong:
They either invert definitions (boxing vs. unboxing), rely on the wrong language helper, or misuse literal suffixes.



Common Pitfalls:
Assuming all numeric conversions are safe; forgetting that only M/m marks a Decimal literal.



Final Answer:
Widening conversions take place automatically.

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