Getting type information at runtime in C Sharp (C#) - Mini Project: Build & Apply

Getting type information at runtime

📖 Scenario: Imagine you are building a simple program that needs to check what kind of objects it is working with while running. This is like checking the label on a box before opening it to know what's inside.

🎯 Goal: You will create a program that stores different objects, then finds out and prints their types while the program is running.

📋 What You'll Learn

Create a list called items with different types of objects

Create a variable called count to store the number of items

Use a for loop with variable i to go through items

Inside the loop, get the type of each item using GetType()

Print the type name of each item using Console.WriteLine

💡 Why This Matters

🌍 Real World

Programs often need to check what kind of data they are working with to decide what to do next. For example, a program that reads files might check if the content is text or numbers.

💼 Career

Understanding how to get type information at runtime helps in debugging, logging, and writing flexible code that can handle different data types safely.

1

Create a list of different objects

Create a list called items that contains these exact objects: 42 (an integer), "hello" (a string), and 3.14 (a double).

C Sharp (C#)

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        // Create the list called items with 42, "hello", and 3.14
        // Your code here
    }
}

Need a hint?

Use List<object> to hold different types together.

2

Create a variable to count the items

Create an integer variable called count and set it to the number of items in the items list using items.Count.

C Sharp (C#)

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        List items = new List { 42, "hello", 3.14 };
        
        // Create the count variable
        // Your code here
    }
}

Need a hint?

Use int count = items.Count; to get the number of items.

3

Loop through the list and get each item's type

Use a for loop with variable i from 0 to count - 1 to go through the items list. Inside the loop, create a variable called itemType and set it to the type of the current item using items[i].GetType().

C Sharp (C#)

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        List items = new List { 42, "hello", 3.14 };
        int count = items.Count;
        
        // Loop through items and get each type
        // Your code here
    }
}

Need a hint?

Use for (int i = 0; i < count; i++) and items[i].GetType().

4

Print the type name of each item

Inside the for loop, add a line to print the type name of each item using Console.WriteLine(itemType.Name).

C Sharp (C#)

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        List items = new List { 42, "hello", 3.14 };
        int count = items.Count;
        for (int i = 0; i < count; i++)
        {
            Type itemType = items[i].GetType();
            // Print the type name
            // Your code here
        }
    }
}

Need a hint?

Use Console.WriteLine(itemType.Name); to print the type name.