ADODC activeX control - Null Reference for Property node for Fields property of Recordset

[zoe_lithoi]

Greetings all,

I'm having problems using some parts of the ADODC activeX control in a Labview ActiveX container. 

the top level properties seem to work fine (like the recordsource and connectionstring), however, I am getting runtime errors when I try to use the Fields property of the Recordset property of the ADODC reference.

When I run the program, a pop-up window appears with the following error message:

Error 97 occurred at Property Node

Possible reasons:

Labview: Null referene was passed in as input

Help?

P.S.  I realize there are alternative methods for doing this such as the database connectivity toolset, however, I would like to try to figure this out.

Thanks!

[Brian_K.]

Hi Zoe,

Did you put indicators on inputs to the ActiveX Container to see if any of them were Null?  I assume you are starting with a very small program.  Could you post a picture of it?

Have a good one.

[zoe_lithoi]

Hi Brian,

I don't have a website to post an image. Do you know of one I could post the image to?

I have 2 indicators which work on the top level properties, but nothing works below it.

I have an adodc activex control in a labview activex container.

In the block diagram, the activex control reference is passed to an open animation block,

which, in turn is wired to 2 property nodes with the 'recordsource' and 'connectionstring' properties respectively. Here is some ascii art of one of the many attempts I've made:

Adodc_Toby --- 'Open animation' --------- Property Node

                                                           |       Recordsource --- 'Indicator

                                                           |

                                                           ------  Property Node

                                                           |         ConnectionString --- indicator

                                                           |

                                                           -------Property Node

                                                                    Recordset ------- Property Node

                                                                                                Fields  

The error I described earlier occurs on the Recordset Property Node.

If I delete that node and the fields node, then the 2 indicators show valid information.

The connnection string will show on the front panel:

Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\jasper\National Instruments\Work_related_Labview\labview.mdb;Persist Security Info=False

and the Recordsource indicator shows:

SELECT * from Jasper_DG535

I had entered these on the Front Panel control by right-clicking on the control and selecting ADODC properties

Coud you try to simulate this?

Thanks,

  Toby

[Brian_K.]

Hi Toby,

If you wan't you can attach a snipet of your code or a picture.  You can do this when you reply to a message and go to the attachment section of the post, and browse to the VI or image you want.  I think that would be the easiest way to see what you are trying to do.

[zoe_lithoi]

Hi Brian (or anyone),

Sorry for the delay getting back to you. Got super busy at work. Hope it's not too late to enlist your help.  Thanks, I somehow missed the 'attachment section' on your discussion group website.

In the attachment, I show the front panel, ADODC property page, Block Diagram, and the error message. When the error message appears, it highlites the offending 3 'blocks' on the Block diagram, which are entitled: Recordset, Recordset, and Fields.

Thank you!

   Toby

[Brian_K.]

Hi Toby,

Can you check to see if the reference is NULL going into the _recordset property nodes, just to make sure the error is correct?