The type or namespace name 'OracleConnection' could not be found

Question

I am getting this error every time I try to debug my program:

CS0246: The type or namespace name 'OracleConnection' could not be found (are you missing a using directive or an assembly reference?)

This occurs on the declaration private readonly OracleConnection oracleConnection; (and in a few other places as well)

I have been trying a number of suggested solutions but so far none have worked:

I have added a reference to the System.Data.OracleClient.dll
My target framework is set to .NET Framework 4
I have tried both including using System.Data.OracleClient and manually writing out System.Data.OracleClient.OracleConnection

EDIT: The code I am using is as follows:

using System;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using System.Collections.Generic;
using System.Data.OleDb;
using System.Linq;
using System.Web;
using System.Data;
using System.Configuration;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

namespace Foo
{
    public class DBHandler
    {
        private readonly OracleConnection oracleConnection;
        private readonly OracleCommand oracleCommand;
        private readonly OracleDataAdapter oracleAdapter;

Nothing has worked so far, so any suggestions would be appreciated.

Can you please confirm which version of framework are you using? — Adil, Aug 31 '12 at 17:50
Is it client profile version or simple .NET 4? Can you check Project Properties? — Adil, Aug 31 '12 at 17:53
In Project Properties, under the Application tab, I have Target Framework set to `.NET Framework 4` — jaredk, Aug 31 '12 at 17:55
Can you post more of the code? Like from the using statements down to the first reference of the OracleClient? — Zeph, Aug 31 '12 at 17:55
Did you add the reference from the .NET dialog or browse to the .dll? — Zeph, Aug 31 '12 at 17:59
Added code, though I can't quite get the formatting right. Also, I added the reference to the .dll by going to the References folder in the Project Explorer pane, right-clicking and hitting "Add Reference". From there I went to the .NET tab and selected the dll from the list. — jaredk, Aug 31 '12 at 18:04
Does the error message list the name of the file that has the error? Is that in your DBHandler file (or whatever it's named specifically)? — Zeph, Aug 31 '12 at 18:24
The error message does contain the file path and it is the DBHandler file. — jaredk, Aug 31 '12 at 18:26

score 4 · Answer 1 · edited Nov 19 '12 at 17:14

4

First of all, for Oracle, System.Data.OracleClient has been deprecated and therefore it's not been recommended now. For details, please visit ADO.NET Team Blog Post

What is recommended is Oracle client published by Oracle corporation. Download the Oracle Data Access component from Oracle .NET Developer Center

Then in the same way, you can use OracleConnection, OracleCommand etc. by adding reference to Oracle.Client dll.

Further please note this library wont be available for .NET 4 Client Profile.

edited Nov 19 '12 at 17:14

Nathan DeWitt

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answered Aug 31 '12 at 17:43

Adil

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I have read about this solution, however it is not an option for me to use third-party software. – jaredk Aug 31 '12 at 17:48
5

If you have an Oracle database then using the Oracle client really isn't third party software – Jesse Aug 31 '12 at 17:55

Zeph · Answer 2 · 2012-08-31T18:35:36.750

1

I think the using directive got removed.

using System;
using System.Data.SqlClient;
using System.Data.SqlTypes;
using System.Data.OracleClient; //Add This
using System.Collections.Generic;
using System.Data.OleDb;
using System.Linq;
using System.Web;
using System.Data;
using System.Configuration;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

namespace Foo {

public class DBHandler
    {

        private readonly OracleConnection oracleConnection;
        private readonly OracleCommand oracleCommand;
        private readonly OracleDataAdapter oracleAdapter;

Did you maybe try each of those steps individually and then set them back when they didn't work?

edited Aug 31 '12 at 18:35

answered Aug 31 '12 at 18:06

Zeph

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I have tried doing this as well, but then I get the error `CS0234: The type or namespace name 'OracleClient' does not exist in the namespace 'System.Data' (are you missing an assembly reference?)` – jaredk Aug 31 '12 at 18:10
Expand the references folder in the solution explorer and make sure that the System.Data.OracleClient is still listed there – Zeph Aug 31 '12 at 18:12
Ok, Highlight the System.Data.OracleClient reference in the solutions explorer, then look in the properties window (if it's not there, go to view and choose "Properties Window") and please list the Runtime Version, Specific Version, Resolved, Path – Zeph Aug 31 '12 at 18:31
Runtime Version: v4.0.30319, Specific Version: False, Resolved: True, Path: C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\System.Data.OracleClient.dll – jaredk Aug 31 '12 at 18:36
Well that's about all I got. Does the syntax highlighter recognize the OracleConnection reference? i.e. is it highlighted (by default aqua). And does autocomplete recognize OracleClient if you type in "using System.Data." – Zeph Aug 31 '12 at 18:43
It does get recognized by the syntax highlighter (and it has a note attached saying that the method is deprecated). It is when I attempt to run the program that I get the compilation error. – jaredk Aug 31 '12 at 18:49
I'm out of things to try. I would create a new project of type console application, change the target fromework to .NET 4, add the reference to the OracleClient.dll and then create a simple main program that has the Using directive at the top and declares an oracleconnection in the body of the main and see if that works ok. – Zeph Aug 31 '12 at 19:00
I tried out your suggestion, and I was able to successfully create the connection. I have no idea what the problem was, but I am just going to start over and hope this doesn't come back up again. – jaredk Aug 31 '12 at 19:13

score 1 · Accepted Answer · answered Sep 12 '12 at 16:45

1

I managed to solve this one, though I don't know how what I changed affected anything. The DBHandler.cs file was located in a folder called "App_Code". Moving the file up one level (into the main project folder) seems to have solved the error.

answered Sep 12 '12 at 16:45

jaredk

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score 0 · Answer 4 · answered Nov 20 '14 at 04:52

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Project->Add reference->Oracle.DataAccess
Here there are two versions- 2.something and 4.something. When I selected the version 4 it did't resolve the namespace, but when I selected the version 2 it resolved!!

answered Nov 20 '14 at 04:52

Sagar Kalburgi

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The type or namespace name 'OracleConnection' could not be found

4 Answers4