Naming conventions in C# - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of variable names with different casing

What is the output of this C# code snippet?

C Sharp (C#)

using System;
class Program {
    static void Main() {
        int myVariable = 5;
        int MyVariable = 10;
        Console.WriteLine(myVariable + ", " + MyVariable);
    }
}

A 10, 5

B Runtime error

C Compilation error due to duplicate variable names

D 5, 10

💡 Hint

Remember that C# is case-sensitive when it comes to variable names.

C# treats myVariable and MyVariable as two different variables because it is case-sensitive. So, the output prints their values separated by a comma.

🧠 Conceptual

intermediate

Correct naming convention for constants

Which of the following is the correct naming convention for a constant in C#?

A const int MaxSize = 100;

B int MAX_SIZE = 100;

C const int max_size = 100;

D int maxSize = 100;

💡 Hint

Constants in C# are usually declared with const keyword and use PascalCase.

In C#, constants are declared with the const keyword and follow PascalCase naming convention, so MaxSize is correct.

🔧 Debug

advanced

Identify the naming convention violation

Which option violates the standard C# naming conventions for methods?

A public void CalculateTotal123() {}

B public void calculateTotal() {}

C public void Calculate_Total() {}

D public void CalculateTotal() {}

💡 Hint

Methods in C# should use PascalCase without underscores.

Option B uses camelCase (calculateTotal) which is not the standard for methods in C#. Methods should use PascalCase.

📝 Syntax

advanced

Which variable name causes a syntax error?

Which of the following variable names will cause a syntax error in C#?

A int totalValue;

B int _count;

C int 2ndValue;

D int value_2;

💡 Hint

Variable names cannot start with a digit in C#.

Option C starts with a digit which is not allowed in C# variable names, causing a syntax error.

🚀 Application

expert

Determine the number of items in a dictionary with naming conventions

Given the following C# code, how many items will the dictionary contain after execution?

C Sharp (C#)

using System.Collections.Generic;
var dict = new Dictionary<string, int>();
dict["FirstKey"] = 1;
dict["firstkey"] = 2;
dict["First_Key"] = 3;
dict["FirstKey"] = 4;

A 3

B 4

C 1

D 2

💡 Hint

Dictionary keys in C# are case-sensitive and exact string matches.

The dictionary keys are "FirstKey", "firstkey", and "First_Key" which are all different strings. The last assignment to "FirstKey" updates its value, so total items are 3.

Practice

1. Which naming convention is correct for a C# class name?

easy

A. MyClass

B. myClass

C. my_class

D. MYCLASS

Solution

1. Step 1: Understand class naming convention in C#

   Classes in C# use PascalCase, where each word starts with a capital letter and no underscores are used.

2. Step 2: Compare options with PascalCase

   MyClass uses PascalCase correctly. my_class uses snake_case, myClass uses camelCase, and MYCLASS uses all uppercase (incorrect for classes).

3. Final Answer:

   MyClass -> Option A

4. Quick Check:

   Class names use PascalCase = MyClass [OK]

Hint: Classes always start with uppercase letters (PascalCase) [OK]

Common Mistakes:

• Using camelCase for class names
• Using underscores in class names
• Using all uppercase for class names

2. Which of the following is the correct way to name a local variable in C#?

easy

A. localVariable

B. LocalVariable

C. LOCALVARIABLE

D. local_variable

Solution

1. Step 1: Recall local variable naming rules

   Local variables in C# use camelCase, starting with a lowercase letter and no underscores.

2. Step 2: Match options to camelCase

   localVariable uses camelCase correctly. LocalVariable uses PascalCase, LOCALVARIABLE uses all uppercase, and local_variable uses underscores.

3. Final Answer:

   localVariable -> Option A

4. Quick Check:

   Local variables use camelCase = localVariable [OK]

Hint: Local variables start lowercase, no underscores (camelCase) [OK]

Common Mistakes:

• Starting local variables with uppercase letters
• Using underscores in local variable names
• Using all uppercase for local variables

3. What will be the output of the following code snippet?

const int MAX_COUNT = 10;
int maxCount = 5;
Console.WriteLine(MAX_COUNT);
Console.WriteLine(maxCount);

medium

A. Compilation error

B. 10 and 5

C. 5 and 10

D. maxCount and MAX_COUNT

Solution

1. Step 1: Identify constant and variable values

   MAX_COUNT is a constant with value 10, maxCount is a variable with value 5.

2. Step 2: Understand Console.WriteLine outputs

   Console.WriteLine(MAX_COUNT) prints 10, Console.WriteLine(maxCount) prints 5.

3. Final Answer:

   10 and 5 -> Option B

4. Quick Check:

   Constants print their value = 10, variables print their value = 5 [OK]

Hint: Console.WriteLine prints the values, not the names [OK]

Common Mistakes:

• Confusing constant and variable values
• Expecting names to print instead of values
• Thinking naming affects output values

4. Identify the error in the following C# code snippet:

public class exampleClass {
    public int MyProperty { get; set; }
    private int myField;
}

medium

A. Field name should be PascalCase

B. Property name should be camelCase

C. Class name should be PascalCase

D. No errors, code is correct

Solution

1. Step 1: Check class naming convention

   Class names must use PascalCase, but 'exampleClass' starts with lowercase.

2. Step 2: Check property and field naming

   Property 'MyProperty' uses PascalCase correctly; field 'myField' uses camelCase correctly.

3. Final Answer:

   Class name should be PascalCase -> Option C

4. Quick Check:

   Class names = PascalCase, exampleClass is incorrect [OK]

Hint: Class names always start uppercase (PascalCase) [OK]

Common Mistakes:

• Using lowercase for class names
• Confusing property and field naming rules
• Thinking camelCase is okay for classes

5. You have a constant for the maximum number of users and a method parameter for the current user count. Which naming is correct in C#?

public const int max_users = 100;
public void UpdateUserCount(int CurrentUserCount) { }

hard

A. MaxUsers and currentusercount

B. maxUsers and CurrentUserCount

C. max_users and current_user_count

D. MaxUsers and currentUserCount

Solution

1. Step 1: Naming for constants

   Constants use PascalCase, so MaxUsers is correct, max_users is incorrect.

2. Step 2: Naming for method parameters

   Method parameters use camelCase, so currentUserCount is correct, CurrentUserCount is incorrect.

3. Final Answer:

   MaxUsers and currentUserCount -> Option D

4. Quick Check:

   Constants PascalCase, parameters camelCase = MaxUsers, currentUserCount [OK]

Hint: Constants PascalCase, parameters camelCase (start lowercase) [OK]

Common Mistakes:

• Using camelCase for constants
• Starting parameters with uppercase letters
• Using underscores in parameters