Value types vs reference types mental model in C Sharp (C#) - Hands-On Comparison

Value types vs reference types mental model

📖 Scenario: Imagine you have a box with a number inside and a label with a name. You want to understand how copying the box or the label works in C#.

🎯 Goal: Learn how value types and reference types behave differently when copied or changed.

📋 What You'll Learn

Create a value type variable with an integer

Create a reference type variable with a string array

Copy the value type variable to a new variable

Copy the reference type variable to a new variable

Change the copied variables and observe the effects

💡 Why This Matters

🌍 Real World

Understanding value and reference types helps avoid bugs when copying or modifying data in programs.

💼 Career

Many programming jobs require clear understanding of how data is stored and copied to write efficient and correct code.

1

Create a value type variable

Create an integer variable called originalNumber and set it to 10.

C Sharp (C#)

# Create an integer variable called originalNumber and set it to 10
// Your code here

Need a hint?

Use int to create a value type variable.

2

Create a reference type variable

Create a string array called originalNames with these values: "Alice", "Bob", "Charlie".

C Sharp (C#)

int originalNumber = 10;
// Create a string array called originalNames with "Alice", "Bob", "Charlie"
// Your code here

Need a hint?

Use string[] to create an array which is a reference type.

3

Copy the variables

Create a new integer variable called copiedNumber and set it equal to originalNumber. Then create a new string array variable called copiedNames and set it equal to originalNames.

C Sharp (C#)

int originalNumber = 10;
string[] originalNames = { "Alice", "Bob", "Charlie" };
// Copy originalNumber to copiedNumber
// Copy originalNames to copiedNames
// Your code here

Need a hint?

Assign the variables directly to copy them.

4

Change copied variables and print results

Change copiedNumber to 20. Change the first element of copiedNames to "David". Then print originalNumber, copiedNumber, originalNames[0], and copiedNames[0] each on a new line.

C Sharp (C#)

int originalNumber = 10;
string[] originalNames = { "Alice", "Bob", "Charlie" };
int copiedNumber = originalNumber;
string[] copiedNames = originalNames;
// Change copiedNumber to 20
// Change copiedNames[0] to "David"
// Print originalNumber, copiedNumber, originalNames[0], copiedNames[0]
// Your code here

Need a hint?

Changing the copied number does not affect the original number. Changing the copied array changes the original array because arrays are reference types.