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connect a mysql database to c# project

25-Oct-06 21:26

Control[] MyArray = new Control[X];

Was that what you were looking for?

Regards

chathu03j25-Oct-06 20:46

chathu03j

25-Oct-06 20:46

I'm quite new to c#. Can smbody pls tell me how to connect a mysql database to a c# project? Thanks

Re: connect a mysql database to c# project

seee sharp25-Oct-06 21:13

seee sharp

25-Oct-06 21:13

You may like to have a look at this

http://www.codeproject.com/cs/database/ConnectMySQL.asp[^]

- ashish

Re: connect a mysql database to c# project

Polar2226-Oct-06 1:51

Polar22

26-Oct-06 1:51

you need to install an ADO.NET driver for mysql, you can find one here:
http://dev.mysql.com/downloads/connector/net/5.0.html[^]

Once installed, new components, like MysqlDataset and MysqlDataTable, will appear in your toolbox in visual studio. Documentation on how to use them should also be included in the download, otherwise you can lookup the documentation for the ADO.NET components, like Dataset and DataTable, in the visual studio documentation, they are used the same way.

HowTo make a dll, which can be called by VBA

Ariadne25-Oct-06 19:34

25-Oct-06 19:34

Hi,
are there any roules for a dll written in C#, which can be called by a VBA Macro?

Private Declare Function foo Lib "foo.dll" (sfoo as string) as string

How does the C# code for such dll look like?

Ariadne

mav.northwind25-Oct-06 21:07

mav.northwind

25-Oct-06 21:07

Hi!
You'll have to create a COM object for this, VBA cannot access a function in a .NET assembly.

Regards,
mav

--
Black holes are the places where God divided by 0...

Nader Elshehabi25-Oct-06 21:24

25-Oct-06 21:24

What Mav said is true. But as an addition, you can write your code as C# and make your C# dll, then register it as COM dll then use it from your VBA macro.

I think this post[^] would be helpful.

Regards

Ariadne25-Oct-06 21:32

25-Oct-06 21:32

Really?
Is it complicate to register a dll as com?

Ariadne

Nader Elshehabi25-Oct-06 21:34

25-Oct-06 21:34

Well, not really. You can follow the link to the post I gave you in the previous reply.

Here is the link again[^].

Regards

ed^nrgc26-Oct-06 3:53

ed^nrgc

26-Oct-06 3:53

you should check : ServicedComponent

Ariadne25-Oct-06 23:03

25-Oct-06 23:03

Thanks.
If I use tlbexp I get only my class exposed, but not my methods. Any ideas? (I suppose, the methods have to have a certain format.)

Nevertheless I do not belive, that a COM-object is the only way to get a connection to VBA. With a COM-object you do not need a Declare Function statement. But with a Declare Function one can access all routines eg. in the kernel.dll. (And that are not COM's in kernel.dll).

Ariadne

Nader Elshehabi25-Oct-06 23:08

Re: HowTo make a dll, which can be called by VBA [modified]

25-Oct-06 23:08

If you got your class exposed, how come not the methods in it?? Aren't they public?

If there is some sort of a VBA .Net language then this would be a solution to your problem, bur otherwise there is no other direct conection between umanaged-to-managed code that I know of.

Regards

Ariadne25-Oct-06 23:13

25-Oct-06 23:13

public class PW
{
  public static string Convert5Bit(byte[] abytID)
  {
    //do somthing here ...
    return sConv;
  }
}

This is the declaration. But only PW as class is exposed.

-- modified at 5:19 Thursday 26th October, 2006

Ariadne

Nader Elshehabi26-Oct-06 0:58

26-Oct-06 0:58

First:
Post your question to my answers, not to your question. I only saw your question by chance.

Second:
Try to reference to your new COM object in a C++ or C# project and see what is/isn't exposed

Third:
If none other works -I'm not that expert in VBA so if applicable- Make your method non-static, and call it form an instance of the class rather than the calss itself.

Ps.
BTW, what way did you know by it's not exposed?

Regards

Ariadne26-Oct-06 2:09

26-Oct-06 2:09

thanks for 1st.
2nd I look into the code with notepad and try in VBA the Object-Browser. both show only PW and not Convert5Bit()
3rd it tried that, but no success.
thanks for your ansers! Rose | [Rose]

Ariadne

Nader Elshehabi26-Oct-06 6:35

26-Oct-06 6:35

Ariadne wrote:
Object-Browser. both show only PW and not Convert5Bit()

Well, in that object browser the method should be under the class name, shouldn't it? I mean you access the method by the class name? Also what file did you look into using the notepad?

Ariadne wrote:
3rd it tried that, but no success.

Define "no success"? You can't instantiate the object from the exposed class? Or the instance can't access the member function?

Regards

Ariadne26-Oct-06 9:41

26-Oct-06 9:41

Nader Elshehabi wrote:
Also what file did you look into using the notepad?

I opened the tlb-File with notepad: There was no Convert5Bit.

Nader Elshehabi wrote:
object browser the method should be under the class name

Under the class name is no method.

If I instantiate the class I get an runtime error: 429 ActiveX component can't create object.

But VBA knows the class PW.

Ariadne

Nader Elshehabi26-Oct-06 19:28

26-Oct-06 19:28

Well, I haven't tested the issue thoroughly. I did some googling and found this post on MSDN forum

Post link[^]

and here are two more articles in MSDN about the issue:
Article 1[^]
Article 2[^]

Also I did what I told you. I made a tlb from the .Net dll, and it actually references to the class and the methods inside the class!! About the instantiation errer; Did you make your constructor public?

I hope this directs you somewhere. Good luck! And I'm waiting for your feedback.

Regards

Ariadne27-Oct-06 3:55

Re: HowTo make a dll, which can be called by VBA: I got it!

27-Oct-06 3:55

Thanks for your articles.

I read a lot of stuff too. OMG | :OMG:

But it seams there is something basic wrong.

here the story, what I try:

1. I build a classlibrary-project in VS8 C#.
2. I insert one TestDLL class:

using System;
using System.Collections.Generic;
using System.Text;
public class TestDLL
{
  public string StringChange(string str)
  {
    return str +" from C#";
  }
}

3. I build the project with a TestDLL.dll as result
4. I run tlbexp TestDLL.dll /win 32 /out:TestDLL.tlb
5. An inspection of TestDLL.tlb with notepad.exe shows no StringChange string.
6. I run regasm TestDLL.dll
It returns a waring: RA00000 : there are no types registered (retranslation from german)
7. I tested the same on a virgin VS8 Enviroment on my home notebook with the same result.
8. I have no idea.... Frown | :(

Ariadne

Ariadne27-Oct-06 4:36

27-Oct-06 4:36

That's it: in assemblyinfo.cs there is a switch:
[assembly: ComVisible(true)]
but it was false
Now all works fine... Laugh | :laugh:

Thank you for your support Nader

Ariadne