How to Create List in C#: Syntax and Examples

In C#, you create a list using the List<T> class from System.Collections.Generic. You declare it with a type inside angle brackets, like List<int> numbers = new List<int>();, to store items of that type.

Syntax

To create a list in C#, use the List<T> class where T is the type of items you want to store. You need to include using System.Collections.Generic; at the top of your file.

• List<T>: The list type that holds items of type T.
• new List<T>(): Creates a new empty list.
• T: The type of elements, like int, string, or a custom class.

csharp

using System.Collections.Generic;

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

Example

This example shows how to create a list of strings, add items, and print them.

csharp

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        List<string> fruits = new List<string>();
        fruits.Add("Apple");
        fruits.Add("Banana");
        fruits.Add("Cherry");

        foreach (string fruit in fruits)
        {
            Console.WriteLine(fruit);
        }
    }
}

Output

Apple
Banana
Cherry

Common Pitfalls

Some common mistakes when creating lists in C# include:

• Forgetting to include using System.Collections.Generic;, which causes errors because List<T> is not found.
• Not specifying the type T inside the angle brackets, which is required.
• Trying to add items of a different type than the list's type, causing compile errors.

csharp

/* Wrong: Missing using directive and type */
// List numbers = new List(); // Error: type required and List not found

/* Correct: Specify type and include using */
using System.Collections.Generic;
List<int> numbers = new List<int>();
numbers.Add(5);

Quick Reference

Here is a quick summary of how to create and use lists in C#:

Action	Syntax Example
Create empty list	List<T> list = new List<T>();
Add item	list.Add(item);
Access item	var item = list[index];
Get count	int count = list.Count;
Loop through list	foreach(var item in list) { /* use item */ }

Key Takeaways

Use List<T> with a specified type to create a list in C#.

Always include using System.Collections.Generic; to access the List class.

Add items with Add() and access them by index or foreach loop.

The list type T must match the type of items you add.

Common errors come from missing the using directive or wrong type usage.