Connecting to a Database using System.Data.SqlClient

The SqlConnection class in System.Data.SqlClient is used to establish a connection to a SQL Server database. This example demonstrates how to set up a connection string and connect to the database securely.

Key Topics

Basic Connection

Example

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        string connectionString = "Server=localhost;Database=MyDatabase;User Id=myUser;Password=myPassword;";

        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            connection.Open();
            Console.WriteLine("Database connected successfully.");
        }
    }
}

Explanation: This example uses the SqlConnection class to open a connection to the database. The using statement ensures that the connection is properly closed and disposed of after use.

Connection with Error Handling

Example

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        string connectionString = "Server=localhost;Database=MyDatabase;User Id=myUser;Password=myPassword;";

        try
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                connection.Open();
                Console.WriteLine("Database connected successfully.");
            }
        }
        catch (SqlException ex)
        {
            Console.WriteLine("An error occurred: " + ex.Message);
        }
    }
}

Explanation: This example adds error handling using a try-catch block to catch SQL-related exceptions and display an appropriate error message.

Key Takeaways

  • Use the SqlConnection class to connect to a SQL Server database.
  • The using statement ensures proper resource cleanup after database operations.
  • Error handling is essential to manage exceptions like invalid connection strings or network issues.