Here's a quick requirement scenario on testing Verification points for a web service response (which is XML in nature) in IBM Rational Performance Tester (RPT) v184.108.40.206
There are two different set of responses for one request. Based on whether the service has passed/failed, two entirely different xml will be returned. As of now you have a contain verification point to validate if the service has passed but the requirement is to add a condition so that when the response fails even that can be validated through the same scripts. Since conditional statements or multiple verification points are not allowed on same tag/response, this becomes a challenging task.
Here's a few thoughts to address such requirement:
1) You could create a Field Reference for the response and then evaluate this in custom code. If the response is text, that would be pretty straightforward.
2) It's also possible to use regular expressions in the Verification Point (VP) -- depending on how the two responses differ that could be an option. Again a regular expression wouldn't work unless there was some similarity in the responses.
3) If the two responses are completely different, custom code is probably the best approach.
Unfortunately, For web service response you could notice the difficulty of not being able to make the response as "Field response" as while selecting the response you would not get an option to mark it as "Field response". And yes both the responses are entirely difference in content.
The best fit is to write a custom code that will help to address this use-case. To have this working:
1) Turn the XML answer of the web service into a Text Answer
2) Then it is possible to create a field reference on the full answer, as shown below.