How to Use Arrays and Lists in ASP.NET C# WebForms

Introduction

In ASP.NET WebForms, you often need to handle multiple values — like product names, user IDs, or form inputs — together.
That’s where Arrays and Lists come in.

• Arrays are fixed-size collections.

• Lists are dynamic — you can add or remove items at runtime.

In this blog, we’ll understand both with real ASP.NET C# examples, such as displaying product names in a GridView.

What is an Array in C#?

An Array is a collection that stores multiple values of the same type in a fixed size.

Example

string[] products = { "Laptop", "Mouse", "Keyboard", "Monitor" };

You can access values using index positions:

Response.Write(products[0]); // Output: Laptop

Example 1: Display Array Data in ASP.NET WebForm

ASPX Page (ArrayExample.aspx)

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ArrayExample.aspx.cs" Inherits="WebFormsDemo.ArrayExample" %>

<!DOCTYPE html>
<html>
<head>
    <title>Array Example in ASP.NET</title>
</head>
<body>
    <h2>Array Example: Product List</h2>
    <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="true"></asp:GridView>
</body>
</html>

Code Behind (ArrayExample.aspx.cs)

using System;
using System.Data;

namespace WebFormsDemo
{
    public partial class ArrayExample : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            // Step 1: Create an array of products
            string[] products = { "Laptop", "Mouse", "Keyboard", "Monitor", "Printer" };

            // Step 2: Convert array to DataTable to display in GridView
            DataTable dt = new DataTable();
            dt.Columns.Add("Product Name");

            foreach (string item in products)
            {
                dt.Rows.Add(item);
            }

            // Step 3: Bind data to GridView
            GridView1.DataSource = dt;
            GridView1.DataBind();
        }
    }
}

Output

What is a List in C#?

A List is a generic collection that allows dynamic resizing — you can add, remove, or modify elements easily.

Example

List<string> employees = new List<string>();
employees.Add("John");
employees.Add("Priya");

Example 2: Display List Data in ASP.NET WebForm

ASPX Page (ListExample.aspx)

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ListExample.aspx.cs" Inherits="WebFormsDemo.ListExample" %>

<!DOCTYPE html>
<html>
<head>
    <title>List Example in ASP.NET</title>
</head>
<body>
    <h2>List Example: Employee Details</h2>

    <asp:Button ID="btnAdd" runat="server" Text="Add New Employee" OnClick="btnAdd_Click" />
    <br /><br />
    <asp:GridView ID="GridViewEmployees" runat="server" AutoGenerateColumns="true"></asp:GridView>
</body>
</html>