[Solved] Find the issue in this code:object obj = "test"; if (obj is string s) { Console.WriteLine(s.Length); } else { Console.WriteLine("Not a string"); } | C Sharp (C#)

C Sharp (C#) - Polymorphism and Abstract Classes

Find the issue in this code:

object obj = "test";
if (obj is string s)
{
    Console.WriteLine(s.Length);
}
else
{
    Console.WriteLine("Not a string");
}

AVariable 's' is not declared properly

BNo issue; code runs correctly

CIncorrect use of 'is' operator

DMissing cast before accessing Length

Step-by-Step Solution

Solution:

Step 1: Understand pattern matching with 'is'
The code uses 'is' with pattern matching to declare 's' if obj is string.
Step 2: Verify code correctness
Since obj is "test", s is assigned and accessing s.Length is safe. No errors present.
Final Answer:
No issue; code runs correctly -> Option B
Quick Check:
'is' pattern matching declares variable safely [OK]

Quick Trick: Use 'is Type var' to declare and check type safely [OK]

Common Mistakes:

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