[Solved] Identify the error in this code snippet:object obj = 123; string s = obj as string; Console.WriteLine(s.Length); | C Sharp (C#)

C Sharp (C#) - Polymorphism and Abstract Classes

Identify the error in this code snippet:

object obj = 123;
string s = obj as string;
Console.WriteLine(s.Length);

AThe <code>is</code> operator is used incorrectly.

BThe <code>as</code> cast will fail and <code>s</code> will be null, causing a null reference exception.

CYou cannot use <code>as</code> with value types like int.

DThe code will compile but print 3.

Step-by-Step Solution

Solution:

Step 1: Understand as cast with incompatible types
Since obj holds an int (123), casting it as string returns null.
Step 2: Analyze the usage
Since s is null, calling s.Length causes a null reference exception.
Final Answer:
The as cast will fail and s will be null, causing a null reference exception. -> Option B
Quick Check:
as returns null on failure; check before use [OK]

Quick Trick: Always check for null after as cast before use [OK]

Common Mistakes:

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