Add ref to System.Data.OracleClient and define your connection.
using System.Data.OracleClient;
private static string CONNECTION_STRING =
"User Id=myUserID;Password=myPassword;Data Source=(DESCRIPTION=" +
"(ADDRESS=(PROTOCOL=TCP)(HOST=myserver.server.com)(PORT=yourPort#))" +
"(CONNECT_DATA=(SID=yourSID)));";
using (OracleConnection connection = new OracleConnection())
{
connection.ConnectionString = CONNECTION_STRING;
connection.Open();
Console.WriteLine("State: {0}", connection.State);
Console.WriteLine("ConnectionString: {0}",
connection.ConnectionString);
OracleCommand command = connection.CreateCommand();
string sql = "SELECT * FROM MYTABLE";
command.CommandText = sql;
OracleDataReader reader = command.ExecuteReader();
while (reader.Read())
{
string myField = (string)reader["MYFIELD"];
Console.WriteLine(myField);
}
}