Using Oledb connection string for Localhost c#

Question

When use Oledb c# connection I noticed that a lot connection using file. But how to connect to localhost using oledb? I created database and tables using Microsoft SQL Server Management that connect with SQL Express and using window authentication

When using this function i don't know how should convert to connect to localhost

//Want the connString to connect localhost instead of file
public static string connString = @"Provider=Microsoft.JET.OLEDB.4.0;data source=" + Path + "\\database\\errDB.mdb";
public static OleDbConnection connection;

public myFunction()
{
    string sqlString = "SELECT name,contact,accessLevel,Crudential_ID FROM errors where Crudential_ID =@ID";
    connection = new OleDbConnection(connString);
    OleDbCommand command = new OleDbCommand(sqlString, connection);

    //Open connection
    connection.Open();

    command.Parameters.Add("@ID", OleDbType.VarChar);
    command.Parameters["@ID"].Value = "test";

    //Read from database
    OleDbDataReader reader = command.ExecuteReader();
    if(reader.HasRows)
    {
       .....
    }
    connection.Close();
}

Answer 1

If you are using SQL Express then I would suggest using a System.Data.SqlClient.SqlConnection object to make your connection. You will only need your server name to connect.

Server=ServerName\SQLEXPRESS;Database=Blah;User ID=user;Password=pw

Answer 2

connectionstrings.com - true to its name - is indispensable when you frequently need to construct connection strings. For your specific case, this would be the relevant section .

Based on that, your connection string should look something like this:

Provider=SQLNCLI11;Server=.\SQLEXPRESS;Database=SOMEDATABASE;Trusted_Connection=yes;

To break it down:

• SQLNCLI11 is the SQL Native Client OLEDB provider. You can see available providers in SQL Management Studio , under Server Objects > Linked Servers > Providers .
• .\\SQLEXPRESS is your servername and instance. The . is shorthand for localhost (you can also use localhost if you prefer), and SQLEXPRESS is the default instance name that SQL Express installs under.
• SOMEDATABASE - whatever your database name is.
• Trusted_Connection=yes - Use windows authentication. Sometime you see it as Integrated Security=SSPI . They are one and the same.