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//Data Source: Server Name e SQL ya . ya age noskhe express bashe .\SQLEXPRESS

//connection string sahih bad az in kar: @"Data Source=.;Initial Catalog=Data_Base_Name.mdf;Integrated Security=True;"





public Boolean check_db()

        {

            string connString = "Data Source=.;Initial Catalog=master;Integrated Security=True;";

            string cmdText = "select * from master.dbo.sysdatabases where name='Data_Base_Name.mdf'";

            Boolean result = false;

            SqlConnection con = new SqlConnection();

            con.ConnectionString = connString;

            con.Open();

            SqlCommand cmd = new SqlCommand();

            cmd.Connection = con;

            cmd.CommandText = cmdText;





            SqlDataReader reader = cmd.ExecuteReader();

            result = reader.HasRows;

            con.Close();





            return result;

        }





        public void atach_db()//attach

        {

            string connString = @"Data Source=.;Integrated Security=True;Initial Catalog=master";

            string cmdText = "EXEC sp_attach_db @dbname='" + "Data_Base_Name.mdf" + "', @filename1='" + Application.StartupPath + @"\DB\Data_Base_Name.mdf" + "' , @filename2='" + Application.StartupPath + @"\DB\Data_Base_Name_log.ldf" + "'";





            SqlConnection con = new SqlConnection();

            con.ConnectionString = connString;





            SqlCommand cmd = new SqlCommand();

            cmd.Connection = con;

            cmd.CommandText = cmdText;





            con.Open();

            cmd.ExecuteNonQuery();

            con.Close();

        }









        public void detach_db() //detach

        {

            string connString = @"Data Source=.;Integrated Security=True;Initial Catalog=master";

            string cmdText = "sp_detach_db '" + "Data_Base_Name.mdf" + "', 'true'";





            SqlConnection con = new SqlConnection();

            con.ConnectionString = connString;





            SqlCommand cmd = new SqlCommand();

            cmd.Connection = con;

            cmd.CommandText = cmdText;





            con.Open();

            cmd.ExecuteNonQuery();

            con.Close();

        }