Question

me.Invoke does not return any data

Asked by: phil192

I am using the following piece of code to invoke a web servive:

Dim results() As Object = Me.Invoke("OpGet", New Object() {Remote_Instance_ID})

but the results() object is returning as a null object.

I have tested whether the web service is working correctly using WireShark and have seen that the correct XML is being sent and received. But for some reason it is not being populated into this object.

I am completely stumped by this, please could someone help. I have a separate case open which is the same problem but poorly described, I will close this now.

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Asked On
2008-10-16 at 08:50:58ID23820893
Tags

VB.Net

Topics

SOAP

,

Programming for ASP.NET

,

Microsoft Visual Basic.Net

Participating Experts
1
Points
500
Comments
16

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Answers

 

by: TheLearnedOnePosted on 2008-10-20 at 07:25:16ID: 22758139

What happens if you create an instance of a web service, and call the web method directly?

 

by: phil192Posted on 2008-10-20 at 08:40:54ID: 22759040

Hi, thanks for your comment.

Yes, my first approach was to use the 'Add Web Reference' functionality in Visual Studio 2008 using the WSDL attached below.

Then I attempted to use the web service using the following code:

        Dim RemedyWS As New remedydev01.MMM_ESS_EquipmentSupportTicketService()
        Dim RemedyResponse As New remedydev01.TicketType()
        RemedyResponse = RemedyWS.OpGet(TextBox1.Text)

If an invalid parameter is used in the OpGet function then it returns an error from the webService, but if a valid parameter is used then a null object is returned.

It was in my debugging that I found that the root problem went back to the me.invoke call.

 

by: TheLearnedOnePosted on 2008-10-20 at 15:34:42ID: 22762942

What kind of web service is this, and is it under your control?  Does the web service have a test page?

 

by: phil192Posted on 2008-10-21 at 07:17:15ID: 22767381

It's a web service that is configurable and comes with the BMC Remedy server.  It's API is that of Apache AXIS. I don't know any more than that I'm afraid but if there are specific questions that I need to answer to get to the bottom of this then I'm sure I can find out.

Many thanks, Phil

 

by: TheLearnedOnePosted on 2008-10-21 at 07:20:09ID: 22767405

Can you show me the XML that is returned for that web method call?

 

by: phil192Posted on 2008-10-21 at 07:47:17ID: 22767718

Attached is a sample of XML data returned.

 

by: TheLearnedOnePosted on 2008-10-21 at 08:05:31ID: 22767934

In that response, Remote_Instance_ID is blank:

<Remote_Instance_ID/>

 

by: phil192Posted on 2008-10-21 at 08:18:44ID: 22768069

Yes it is, is that a problem?

 

by: TheLearnedOnePosted on 2008-10-21 at 08:21:33ID: 22768093

That would be my first inclination.  You might want to find out if there is a way to get a response that has a valid Remote_Instance_ID (that is not blank).

 

by: phil192Posted on 2008-10-21 at 09:03:27ID: 22768549

I will try to get that changed in the web service, although I feel it is unlikely to be the issue because of the fact that the Invoke function returns a null object. Would it not just return an object with a null value for the Remote_Instance_ID field?

 

by: TheLearnedOnePosted on 2008-10-21 at 09:38:23ID: 22768930

That is an assumption that you need to test.  You would have to determine what the arguments are to the web method that would give you a non-blank Remote_Instance_ID.

 

by: phil192Posted on 2008-10-21 at 10:48:30ID: 22769558

Ok I understand. I'll get the web service changed and test it further. It may take a few days but I'll let you know when I've done it.

Thanks for your help so far.

Phil

 

by: phil192Posted on 2008-11-07 at 05:30:02ID: 22904051

Sorry for the delay, unfortunately the web service is not something I have direct control over so I'm still waiting for this to be completed. Thanks for your patience. Phil

 

by: phil192Posted on 2009-05-09 at 02:11:43ID: 31506806

Thanks for your help TheLearnedOne, I'm going to close this question now as its been a long time since first opening it. If the problem still exists then I will reraise it as an issue.

20120131-EE-VQP-002

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