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SqlConnection Constructor

Initializes a new instance of the SqlConnection class.

Namespace:  System.Data.SqlClient
Assembly:  System.Data (in System.Data.dll)

public SqlConnection()

When a new instance of SqlConnection is created, the read/write properties are set to the following initial values unless they are specifically set using their associated keywords in the ConnectionString property.

Properties

Initial value

ConnectionString

empty string ("")

ConnectionTimeout

15

Database

empty string ("")

DataSource

empty string ("")

You can change the value for these properties only by using the ConnectionString property. The SqlConnectionStringBuilder class provides functionality for creating and managing the contents of connection strings.

The following example creates and opens a SqlConnection.

private static void OpenSqlConnection()
{
    string connectionString = GetConnectionString();
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
        connection.Open();
        Console.WriteLine("ServerVersion: {0}", connection.ServerVersion);
        Console.WriteLine("State: {0}", connection.State);
    }
}

static private string GetConnectionString()
{
    // To avoid storing the connection string in your code,  
    // you can retrieve it from a configuration file, using the  
    // System.Configuration.ConfigurationSettings.AppSettings property  
    return "Data Source=(local);Initial Catalog=AdventureWorks;"
        + "Integrated Security=SSPI;";
}

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0
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