C# Tutorial 5.2: Lists

1. Creating a List:

To use lists in C#, you need to include the System.Collections.Generic namespace. Here's how you can create a list:

using System;

using System.Collections.Generic;

class Program

{

    static void Main()

    {

        // Creating a list of integers

        List<int> numbers = new List<int>();

        // Adding elements to the list

        numbers.Add(1);

        numbers.Add(2);

        numbers.Add(3);

        // Displaying elements

        Console.WriteLine("List elements:");

        foreach (int num in numbers)

        {

            Console.WriteLine(num);

        }

    }

}

2. Initialization with Collection Initializer:

You can also initialize a list using a collection initializer:

List<int> numbers = new List<int> { 1, 2, 3, 4, 5 };

3. Accessing Elements:

Access elements by index:

int firstElement = numbers[0];

4. List Methods:

• Add: Adds an element to the end of the list.
• Remove: Removes the first occurrence of a specific element.
• Count: Gets the number of elements contained in the list.
• Clear: Removes all elements from the list.

5. Iterating Through a List:

You can use a foreach loop or a for loop to iterate through the elements of a list:

foreach (int num in numbers)

{

    Console.WriteLine(num);

}

6. Sorting a List:

Use the Sort method to sort a list:

numbers.Sort();

7. Finding Elements:

Use methods like Contains, IndexOf, or Find to find elements:

bool containsThree = numbers.Contains(3);

int indexOfTwo = numbers.IndexOf(2);

8. List of Objects:

Lists can store any type of object. For example:

List<Person> people = new List<Person>(); people.Add(new Person("John", 25));

9. List of Strings:

Lists can be used to store strings as well:

List<string> words = new List<string> { "apple", "banana", "orange" };

10. Conclusion:

Lists in C# are powerful and flexible. They provide a convenient way to work with collections of items. By understanding the basic operations and methods, you can efficiently manipulate and retrieve data from lists in your C# programs.

This tutorial covers the fundamental aspects of working with lists in C#. Depending on your specific use case, you may need to explore additional features and methods provided by the List class in the C# documentation.