sqlconnection problem

Question

I have created a database file userData.mdf. And have a created a class named dbHelper. Here i have made three functions:                                     OpenConnection();                                     ExecuteQry();                                       CloseConnection();   The problem is here: using System; using System.Collections.Generic; using System.Data.SqlClient; using System.Linq; using System.Text; using System.Threading.Tasks; namespace Insert_Delete_UpdateOperation { public class dbhelper { public static SqlConnection sqlConnection; public static SqlDataReader sqlDataReader; public static void OpenConnection() { String connectionString = "Data Source=(LocalDB)\v11.0;AttachDbFilename="c:\users\suraj\documents\visual studio 2012\Assignment\Insert,Delete,UpdateOperation\Insert,Delete,UpdateOperation\userData.mdf"; Integrated Security=True";); sqlConnection = new SqlConnection(connectionString); sqlConnection.Open(); } public static void ExecuteQry(string qry,Boolean state) { SqlCommand sqlcommand=new SqlCommand(qry,sqlConnection); if(state) { sqlcommand.ExecuteNonQuery(); } else { sqlDataReader=sqlcommand.ExecuteReader(); } } public static void CloseConnection() { if(sqlConnection.State==System.Data.ConnectionState.Open) { sqlConnection.Close(); } } } }

Bhuvanesh Mohankumar · Answer

In Visual Studio go to Server explorer Connect to database Select the MDF files in the options Now you can follow the steps as directed in Server explorer Now you can find the database is attached Click on the database connection properties Copy the "Connection String" value Replace the connection string in your code with copied one. Try this and Test application, let me know if error persist. Mark as answer, if helpful.

Nishant Mittal · Answer

Hi try this con.ConnectionString = @"Data Source=.\SQLEXPRESS; AttachDbFilename=c:\folder\SampleDatabase.mdf; Integrated Security=True; Connect Timeout=30; User Instance=True";