using System; using System.Collections.Generic; using System.Data.SqlClient; using System.Linq; using System.Text; using System.Threading.Tasks; namespace _02Trade { class DB { SqlConnection sqlconnection = new SqlConnection(@"Data Source=(localdb)\05Str; Initial Catalog=02Trade;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; } } }