Generic method declaration in C Sharp (C#) - Mini Project: Build & Apply

Generic Method Declaration in C#

📖 Scenario: Imagine you want to create a method that can work with any type of data, like numbers, words, or even objects. Instead of writing many methods for each type, you can write one generic method that works for all.

🎯 Goal: You will build a generic method called DisplayItem that takes one input of any type and prints it. This helps you understand how to write methods that are flexible and reusable.

📋 What You'll Learn

Create a generic method named DisplayItem with one type parameter T.

The method should take one parameter of type T named item.

Inside the method, print the item to the console.

Call the DisplayItem method with different types: an integer, a string, and a double.

💡 Why This Matters

🌍 Real World

Generic methods are used in many programs to handle different data types without repeating code. For example, sorting lists of numbers or strings using the same method.

💼 Career

Understanding generic methods is important for writing clean, reusable code in professional C# development, especially in libraries and frameworks.

1

Create a basic C# program structure

Write a C# program with a Program class and a Main method inside it. Leave the Main method empty for now.

C Sharp (C#)

class Program
{
    static void Main()
    {
        // Your code here
    }
}

Need a hint?

Start by writing the class and the main method exactly as shown.

2

Declare a generic method named DisplayItem

Inside the Program class but outside the Main method, declare a generic method called DisplayItem with a type parameter T. It should take one parameter named item of type T.

C Sharp (C#)

class Program
{
    static void Main()
    {
    }

    // Your code here
}

Need a hint?

Use the syntax static void DisplayItem<T>(T item) to declare the generic method.

3

Print the item inside the generic method

Inside the DisplayItem method, write code to print the item parameter to the console using Console.WriteLine.

C Sharp (C#)

class Program
{
    static void Main()
    {
    }

    static void DisplayItem(T item)
    {
        // Your code here
    }
}

Need a hint?

Use Console.WriteLine(item); to print the value.

4

Call the generic method with different types

Inside the Main method, call DisplayItem three times with these exact values: 42 (int), "Hello" (string), and 3.14 (double).

C Sharp (C#)

class Program
{
    static void Main()
    {
        // Your code here
    }

    static void DisplayItem(T item)
    {
        Console.WriteLine(item);
    }
}

Need a hint?

Call the method exactly as DisplayItem(42);, DisplayItem("Hello");, and DisplayItem(3.14);.