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me.Invoke does not return any data

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.

Bob Learned

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

phil192

ASKER

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.

WSDL.txt

Bob Learned

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

phil192

ASKER

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

Bob Learned

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

phil192

ASKER

Attached is a sample of XML data returned.
Returned-SOAP-Data-2.txt

Bob Learned

In that response, Remote_Instance_ID is blank:

<Remote_Instance_ID/>

phil192

ASKER

Yes it is, is that a problem?

Bob Learned

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).

phil192

ASKER

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?

ASKER CERTIFIED SOLUTION

Bob Learned

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phil192

ASKER

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

phil192

ASKER

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

phil192

ASKER

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.