public static T findbyKey(params object[] values)
{
T clase = new T();
DataTable dt = AccessDB.getExecuteSQL(String.Format("select {0} from {1} {2};", String.Join(",", clase.columns), clase.TableName, " where " + clase.sqlKeyWhere(values)));
if (dt != null)
{
T obj = new T();
obj.initialize(dt.Rows[0]);
(obj as CommonObj).IsNew = false; //marcar que es una instancia recuperada desde la BD
return(obj);
}
return(default(T));
}
public static List <T> findAll()
{
T clase = new T();
List <T> list = null;
DataTable dt = AccessDB.getExecuteSQL(String.Format("select {0} from {1};", String.Join(",", clase.columns), clase.TableName));
if (dt != null)
{
list = new List <T>();
for (int i = 0; i < dt.Rows.Count; ++i)
{
T obj = new T();
obj.initialize(dt.Rows[i]);
list.Add(obj);
}
}
return(list);
}
public static bool saveObject(T obj)
{
T clase = new T();
DataTable dt = null;
NpgsqlTransaction tx = null;
AccessDB.conn.ConnectionString = AccessDB.CadenaConexion;
AccessDB.conn.Open();
try
{
// iniciar transaccion
tx = AccessDB.conn.BeginTransaction();
if (obj.IsNew)
{
if (obj is IAutoIncrement)
{ //recuperar siguiente valor
dt = AccessDB.getExecuteSQL(String.Format("select max({0})+1 from {1} ;", clase.KeyTable, clase.TableName), true);
if (dt != null) //recuperar maximo id + 1
{
obj.setKeyValue(dt.Rows[0][0]);
}
}
}
AccessDB.getExecuteSQL(obj.SqlString, true);
tx.Commit();
AccessDB.conn.Close();
return(true);
}
catch (Exception)
{
if (tx != null)
{
tx.Rollback();
}
AccessDB.conn.Close();
return(false);
}
}