Constant patterns in C Sharp (C#) - Mini Project: Build & Apply

Using Constant Patterns in C#

📖 Scenario: You are building a simple program that checks the type of fruit and prints a message based on the fruit name.

🎯 Goal: Learn how to use constant patterns with switch expressions in C# to match exact values.

📋 What You'll Learn

Create a string variable called fruit with a specific fruit name.

Create a switch expression using constant patterns to check the fruit.

Print a message for each fruit using Console.WriteLine.

💡 Why This Matters

🌍 Real World

Constant patterns help you check exact values easily, like checking user input or commands in programs.

💼 Career

Understanding constant patterns is useful for writing clear and concise code in many C# applications, including web, desktop, and game development.

1

Create the fruit variable

Create a string variable called fruit and set it to the value "Apple".

C Sharp (C#)

# Create a string variable called fruit and set it to "Apple"
# Your code here

Need a hint?

Use string fruit = "Apple"; to create the variable.

2

Create a switch expression with constant patterns

Create a variable called message and assign it a switch expression that matches fruit using constant patterns for "Apple", "Banana", and "Orange". For each fruit, return a message like "You chose Apple". Use _ as the default pattern returning "Unknown fruit".

C Sharp (C#)

string fruit = "Apple";
# Create a variable message using a switch expression on fruit with constant patterns
# Your code here

Need a hint?

Use the switch expression syntax with constant patterns like "Apple" => "You chose Apple".

3

Add a Console.WriteLine to print the message

Use Console.WriteLine to print the message variable.

C Sharp (C#)

string fruit = "Apple";
string message = fruit switch
{
    "Apple" => "You chose Apple",
    "Banana" => "You chose Banana",
    "Orange" => "You chose Orange",
    _ => "Unknown fruit"
};
# Print the message using Console.WriteLine
# Your code here

Need a hint?

Use Console.WriteLine(message); to display the message.

4

Test with a different fruit value

Change the value of fruit to "Grape" and run the program to see the default message "Unknown fruit" printed.

C Sharp (C#)

# Change the fruit variable to "Grape"
string fruit = "Grape";
string message = fruit switch
{
    "Apple" => "You chose Apple",
    "Banana" => "You chose Banana",
    "Orange" => "You chose Orange",
    _ => "Unknown fruit"
};
Console.WriteLine(message);

Need a hint?

Set fruit to "Grape" and run the program to see the default case message.