using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data.SqlClient; namespace _02trade { class DataBase { SqlConnection sqlconnection = new SqlConnection(@"Data Source=(localdb)\02Stroimaterial; Initial Catalog=trade02;Integrated Security=True"); public void OpenConnection() { if (sqlconnection.State == System.Data.ConnectionState.Closed) { sqlconnection.Open(); } } public void CloseConnection() { if (sqlconnection.State == System.Data.ConnectionState.Open) { sqlconnection.Close(); } } public SqlConnection GetConnection() { return sqlconnection; } } }