Set up SQL Server 2008, how do I access it from C# using SqlConnection?

I have installed SQL Server 2008 Express, and I'm trying to access it from C#.

I'm not so sure I set it up right in SQL Server Management Studio. I have a password, and a .sdf file. Nothing is in the database at the moment. Here's my snippe开发者_StackOverflow中文版t of code in C#

SqlConnection userSqlData = new SqlConnection("Data Source = localhost;database=UserData;Password=Mine;connection timeout = 10");

try
{   
    userSqlData.Open();     
}
catch
{     
    MessageBox.Show("Failed");     
}

The connection always times out. Obviously I've set something up wrong here. How do I get it to connect to database on local computer?

Try connecting to SQL Server express ;) You connect to the default instance. Express is a named instance.

http://www.connectionstrings.com/sql-server-2008

has all kinfds of examples, including for express databases.

The default connection string for SQL Server looks like this:

Data Source=myServerAddress\SQLEXPRESS;Initial Catalog=myDataBase;User Id=myUsername;Password=myPassword;

You need the named instance in Data Source. You also need to specify the User Id of the user you're authenticating as, not just the password. Here's a good resource for additional options:

http://www.connectionstrings.com/sql-server-2008