📚 C# Arrays - Interactive Lesson

An array is a data structure that can hold multiple values of the same type in a single variable. Arrays are used to store a collection of data that can be accessed by index.

📂 Declaring and Initializing an Array

int[] numbers = new int[5];

🔑 Pro Tip: Arrays in C# start at index 0. So, numbers[0] refers to the first element.

📝 Accessing Elements of an Array

numbers[0] = 10; // Assigns 10 to the first element

🔧 Try It Yourself: Update Array Values

Element 0:
Element 1:
Element 2:
Element 3:
Element 4:

[0, 0, 0, 0, 0]

🧠 Quiz: Test Your Knowledge

1. What is the index of the first element in an array?

0
1
-1

2. How do you access the third element of an array called arr?

arr[2]
arr[3]
arr(2)

3. What does this code do?

int[] numbers = { 1, 2, 3, 4, 5 };
Console.WriteLine(numbers[2]);

It prints 3
It prints 4
It causes an error

4. How would you declare an array of strings in C#?

string[] words;
string words[];
words[] string;

5. Which property gets the length of an array?

numbers.Size
numbers.Length
numbers.Count

Quiz results will appear here...

💡 Remember: Array indices always start from 0 in C#. The last index is Length - 1.