ExecuteReader exception

Question

User-1916667149 posted

Hi All,

I am trying to read CLOB field from oracle database table by using ExecuteReader method. However, when I try to do so, it gives me an exception as "Data type is not supported". The field ACTIVITY_COMMENT is a CLOB field and it contains RTF data in it. 

It gives an exception at the line  - myOleDbDataReader = myOleDbCommand.ExecuteReader();

My code is as follows -

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.OleDb;
//using System.Windows.Forms.dll;

namespace ConsoleApplication1
{
    class ConvertFromRTF
    {

        static void Main()
        {
            /* connecting to oracle 
             * */

            string connectionString = "provider=MSDAORA;data source=Oracle12;user id=crmprod;password=crmprod";
            OleDbConnection myOleDbConnection = new OleDbConnection(connectionString);

            OleDbCommand myOleDbCommand = myOleDbConnection.CreateCommand();    

            myOleDbCommand.CommandText = "SELECT ACTIVITY_COMMENT, DATE_ADDED, STAMP2 FROM ACTIVITY WHERE STAMP2 = 'C83AC8C1F6030001'";

            myOleDbConnection.Open();
            OleDbDataReader myOleDbDataReader = null;
            try
            {
                myOleDbDataReader = myOleDbCommand.ExecuteReader();             }
            catch(Exception e)
            {
                Console.WriteLine(e);
            }


            myOleDbDataReader.Read();

            Console.WriteLine("myOleDbDataReader[\" ACTIVITY_COMMENT\"] = " + myOleDbDataReader["ACTIVITY_COMMENT"]);
            Console.WriteLine("myOleDbDataReader[\" DATE_ADDED\"] = " + myOleDbDataReader["DATE_ADDED"]);
            Console.WriteLine("myOleDbDataReader[\" STAMP2\"] = " + myOleDbDataReader["STAMP2"]);



            string plaintext = "";

            try
            {
                plaintext = (string)myOleDbDataReader["ACTIVITY_COMMENT"];
            }
            catch
            {
                Console.WriteLine("Exception caught");
            }

            myOleDbDataReader.Close();
            myOleDbConnection.Close();

            string path = @"test.rtf";

            //Create the RichTextBox. (Requires a reference to System.Windows.Forms.dll.)
            System.Windows.Forms.RichTextBox rtBox = new System.Windows.Forms.RichTextBox();

            // Get the contents of the RTF file. Note that when it is
            // stored in the string, it is encoded as UTF-16.
            string s = System.IO.File.ReadAllText(path);

            // Display the RTF text.
            System.Windows.Forms.MessageBox.Show(s);

            // Convert the RTF to plain text.
            rtBox.Rtf = s;
            plaintext = String.Concat(plaintext,rtBox.Text);

            // Display plain text output in MessageBox because console
            // cannot display Greek letters.
            System.Windows.Forms.MessageBox.Show(plaintext);

            // Output plain text to file, encoded as UTF-8.
            System.IO.File.WriteAllText(@"output.txt", plaintext);
        }
    }


}

Can anyone help me out on this. Thanks in advance....