CRUD ADO.NET Functions in ASP.NET Web Forms

March 3, 2026 Suzan Kara

Overview
Building a web application in C# requires connecting it to a database.
We can connect to, read, insert, update, and remove data from SQL Server with the aid of ADO.NET.

This essay will teach us:

◦ Describe ADO.NET
How to link SQL Server to an ASP.NET web application
CRUD Operations (Create, Read, Update, Delete) ✏ Detailed explanation ✏ Easy-to-understand sample

We are going to construct a basic web application for student management.

What is ADO.NET?

ADO.NET is a technology in .NET Framework used to connect applications with databases like:

SQL Server
Oracle
MySQL

It provides classes like:

SqlConnection
SqlCommand
SqlDataAdapter
SqlDataReader

Step 1: Create Database and Table

Open SQL Server and run this query:

CREATE DATABASE StudentDB;

USE StudentDB;

CREATE TABLE Students
(
    Id INT PRIMARY KEY IDENTITY(1,1),
    Name NVARCHAR(100),
    Email NVARCHAR(100),
    City NVARCHAR(100)
);

Step 2: Create ASP.NET Web Application

Open Visual Studio
Click New Project
Select ASP.NET Web Application (.NET Framework)
Choose Web Forms
Click Create

Step 3: Add Connection String in Web.config

Open Web.config file and add:

<connectionStrings>
  <add name="dbcs"
       connectionString="Data Source=YOUR_SERVER_NAME;Initial Catalog=StudentDB;Integrated Security=True"
       providerName="System.Data.SqlClient"/>
</connectionStrings>

Replace YOUR_SERVER_NAME with your SQL Server name.

Step 4: Design UI (Default.aspx)

Add this inside <form runat="server">:

Name:
<asp:TextBox ID="txtName" runat="server"></asp:TextBox><br />

Email:
<asp:TextBox ID="txtEmail" runat="server"></asp:TextBox><br />

City:
<asp:TextBox ID="txtCity" runat="server"></asp:TextBox><br /><br />

<asp:Button ID="btnInsert" runat="server" Text="Insert" OnClick="btnInsert_Click" />
<asp:Button ID="btnUpdate" runat="server" Text="Update" OnClick="btnUpdate_Click" />
<asp:Button ID="btnDelete" runat="server" Text="Delete" OnClick="btnDelete_Click" />

<br /><br />

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="true"></asp:GridView>

Step 5: Write ADO.NET Code (Default.aspx.cs)

Import Namespaces

using System;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;

Insert Operation

protected void btnInsert_Click(object sender, EventArgs e)
{
    string cs = ConfigurationManager.ConnectionStrings["dbcs"].ConnectionString;

    using (SqlConnection con = new SqlConnection(cs))
    {
        string query = "INSERT INTO Students(Name,Email,City) VALUES(@Name,@Email,@City)";
        SqlCommand cmd = new SqlCommand(query, con);

        cmd.Parameters.AddWithValue("@Name", txtName.Text);
        cmd.Parameters.AddWithValue("@Email", txtEmail.Text);
        cmd.Parameters.AddWithValue("@City", txtCity.Text);

        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
    }

    LoadData();
}

Explanation

SqlConnection → Connects to database
SqlCommand → Executes SQL query
ExecuteNonQuery() → Used for Insert/Update/Delete

Load Data (Read Operation)

public void LoadData()
{
    string cs = ConfigurationManager.ConnectionStrings["dbcs"].ConnectionString;

    using (SqlConnection con = new SqlConnection(cs))
    {
        string query = "SELECT * FROM Students";
        SqlDataAdapter da = new SqlDataAdapter(query, con);
        DataTable dt = new DataTable();

        da.Fill(dt);
        GridView1.DataSource = dt;
        GridView1.DataBind();
    }
}

Call this inside Page_Load:

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        LoadData();
    }
}

Update Operation

protected void btnUpdate_Click(object sender, EventArgs e)
{
    string cs = ConfigurationManager.ConnectionStrings["dbcs"].ConnectionString;

    using (SqlConnection con = new SqlConnection(cs))
    {
        string query = "UPDATE Students SET Email=@Email, City=@City WHERE Name=@Name";
        SqlCommand cmd = new SqlCommand(query, con);

        cmd.Parameters.AddWithValue("@Name", txtName.Text);
        cmd.Parameters.AddWithValue("@Email", txtEmail.Text);
        cmd.Parameters.AddWithValue("@City", txtCity.Text);

        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
    }

    LoadData();
}

Delete Operation

protected void btnDelete_Click(object sender, EventArgs e)
{
    string cs = ConfigurationManager.ConnectionStrings["dbcs"].ConnectionString;

    using (SqlConnection con = new SqlConnection(cs))
    {
        string query = "DELETE FROM Students WHERE Name=@Name";
        SqlCommand cmd = new SqlCommand(query, con);

        cmd.Parameters.AddWithValue("@Name", txtName.Text);

        con.Open();
        cmd.ExecuteNonQuery();
        con.Close();
    }

    LoadData();
}

Expected Output

When you run the application:

Enter student details
Click Insert
Data will display in GridView
You can Update and Delete

Simple working CRUD web application

Why We Use Parameters?

We used:

cmd.Parameters.AddWithValue()

This prevents:

❌ SQL Injection
❌ Security issues

Always use parameters in real projects.

Conclusion

In this article, we learned:

What is ADO.NET
How to connect ASP.NET Web Forms to SQL Server
How to perform CRUD operations
Basic explanation of each class

This is the foundation of database programming in ASP.NET.

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