What is the List.Add() method in C#?

The List.Add() method in C# adds an object to the end of a List<T> collection. A List<T> is a generic collection that can store elements of any type T. For example, we can create a List<string> to store strings or a List<int> to store integers.

Syntax

The syntax of the List.Add() method is given below:

List<T>.Add(T item);

Here, T is the type of the element we want to add, and item is the object we want to add. For example, if we have a List<string> called names, we can add strings to it by using: names.Add("John"), names.Add("Alice") and so on.

Code example

Let’s see how the List.Add() method works:

using System;
using System.Collections.Generic;
class Test
{
    static void Main()
    {
        List<string> colors = new List<string>();
        colors.Add("Red");
        colors.Add("Blue");
        colors.Add("Orange");
        colors.Add("Purple");
        foreach (string c in colors)
        {
            Console.WriteLine(c);
        }
    }
}

Explanation

  • Lines 1–2: Uses directives that allow us to use classes and functionality from the System namespace and the System.Collections.Generic namespace, respectively.

  • Line 8: Declares a generic list of strings named colors. It is an empty list at this point.

  • Lines 10–13: Adds four strings ("Red", "Blue", "Orange", "Purple") to the colors list.

  • Lines 15–18: This is a foreach loop that iterates through each element (string c) in the colors list and prints each color to the console.

Free Resources

Copyright ©2025 Educative, Inc. All rights reserved