using Oracle.ManagedDataAccess.Client;
using Oracle.ManagedDataAccess.Types;

using Oracle.DataAccess.Client;

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Oracle.DataAccess.Client; // ODP.NET Oracle managed provider
using Oracle.DataAccess.Types; 

namespace oraspec1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            string oradb = "Data Source=BI_TEST;User Id=scott;Password=tiger;";
            OracleConnection conn = new OracleConnection(oradb);  // C#
            conn.Open();
            OracleCommand cmd = new OracleCommand();
            cmd.Connection = conn;
            cmd.CommandText = "select id, code, name from c_objects c where c.id =658570587;";
            cmd.CommandType = CommandType.Text;
            OracleDataReader dr = cmd.ExecuteReader();
            dr.Read();
            label1.Text = dr.GetString(0);
            conn.Dispose();
        }
    }
}

See the end of this message for details on invoking 
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
Oracle.DataAccess.Client.OracleException ORA-00911: неверный символ    at Oracle.DataAccess.Client.OracleException.HandleErrorHelper(Int32 errCode, OracleConnection conn, 
IntPtr opsErrCtx, OpoSqlValCtx* pOpoSqlValCtx, Object src, String procedure, Boolean bCheck)
   at Oracle.DataAccess.Client.OracleException.HandleError(Int32 errCode, OracleConnection conn, 
String procedure, IntPtr opsErrCtx, OpoSqlValCtx* pOpoSqlValCtx, Object src, Boolean bCheck)
   at Oracle.DataAccess.Client.OracleCommand.ExecuteReader(Boolean requery, 
Boolean fillRequest, CommandBehavior behavior)
   at Oracle.DataAccess.Client.OracleCommand.ExecuteReader()
   at oraspec1.Form1.button1_Click(Object sender, EventArgs e) in C:\C#\Projects\oraspec1\oraspec1\Form1.cs:line 30
   at System.Windows.Forms.Control.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ButtonBase.WndProc(Message& m)
   at System.Windows.Forms.Button.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

 OracleDataReader dr = cmd.ExecuteReader();

ORA-00911
invalid character

Cause: identifiers may not start with any ASCII character other than letters and numbers. 
$#_ are also allowed after the first character. Identifiers enclosed by doublequotes may contain 
any character other than a doublequote. Alternative quotes (q'#...#') cannot use spaces, 
tabs, or carriage returns as delimiters. For all other contexts, consult the SQL Language Reference Manual.

public OracleDateTime GetOracleDateTime(
	int i
)

 richTextBox1.Text = dr.GetString(0);

string oradb = "Data Source=BI_TEST;User Id=scott;Password=tiger;";
            OracleConnection conn = new OracleConnection(oradb);  // C#
            conn.Open();
            OracleCommand cmd = new OracleCommand();
            cmd.Connection = conn;
            cmd.CommandText = "select name from c_objects where id=9205";
            cmd.CommandType = CommandType.Text;
            OracleDataReader dr = cmd.ExecuteReader();
            dr.Read();
            richTextBox1.Text = dr.GetString(0);
            
            //public OracleDateTime GetOracleDateTime(1);
            //label1.Text = dr.GetOracleDate(0);

            OracleCommand cmd2 = new OracleCommand();
            cmd2.Connection = conn;
            cmd2.CommandText = "SELECT TO_CHAR(CURRENT_DATE, 'DD-MON-YYYY HH:MI') FROM DUAL";
            cmd2.CommandType = CommandType.Text;
            OracleDataReader dr2 = cmd.ExecuteReader();
            dr2.Read();
            //richTextBox1.Text = d2.GetString(0);
            label1.Text = dr2.GetString(0);

            conn.Dispose();