MSDN Documentation

Getting Started with ADO.NET

ADO.NET provides a rich set of components for building data-driven applications on the .NET platform. This guide walks you through creating a simple console app that connects to a SQL Server database, executes a query, and reads the results.

Prerequisites

  • Visual Studio 2022 or later
  • .NET 6.0 SDK (or later)
  • SQL Server Express (or any accessible SQL Server instance)

1. Create a .NET Console Project

dotnet new console -n AdoNetDemo
cd AdoNetDemo
dotnet add package System.Data.SqlClient
dotnet run

2. Establish a Connection

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        var connectionString = "Server=localhost;Database=Northwind;Trusted_Connection=True;";
        using var connection = new SqlConnection(connectionString);
        try
        {
            connection.Open();
            Console.WriteLine("Connection successful!");
        }
        catch (Exception ex)
        {
            Console.WriteLine($"Error: {ex.Message}");
        }
    }
}

3. Execute a Query with SqlCommand

string query = "SELECT TOP 5 ProductName, UnitPrice FROM Products ORDER BY UnitPrice DESC;";
using var command = new SqlCommand(query, connection);
using var reader = command.ExecuteReader();

while (reader.Read())
{
    Console.WriteLine($"{reader["ProductName"]} - ${reader["UnitPrice"]:0.00}");
}

Full Sample Code

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        var connectionString = "Server=localhost;Database=Northwind;Trusted_Connection=True;";
        using var connection = new SqlConnection(connectionString);
        connection.Open();

        string query = "SELECT TOP 5 ProductName, UnitPrice FROM Products ORDER BY UnitPrice DESC;";
        using var command = new SqlCommand(query, connection);
        using var reader = command.ExecuteReader();

        Console.WriteLine("Top 5 most expensive products:");
        while (reader.Read())
        {
            Console.WriteLine($"{reader["ProductName"]} - ${reader["UnitPrice"]:0.00}");
        }
    }
}

Next Steps