Question

I am working with some XML, not really technically inclined and been trying to figure this out from reading various sources on the internet but getting nowhere fast.

I have the below XML:

<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
   <soap:Header>
      <XXXSoapHeader xmlns="http://XXX.com/optima/webservices">
         <AuthenticationString>?</AuthenticationString>
      </XXXSoapHeader>
   </soap:Header>
   <soap:Body>
      <SubmitMultipleCalcMarginRequestResponse xmlns="http://XXX.com/optima/webservices">
         <SubmitMultipleCalcMarginRequestResult>
            <TaskExecutionSubmitInfo>
               <taskExecutionId>74457</taskExecutionId>
               <description>Calc LIVE BROKER margin : Account WebServiceTest_Account1(435) : Business Date (12-Feb-2007)</description>
            </TaskExecutionSubmitInfo>
            <TaskExecutionSubmitInfo>
               <taskExecutionId>74458</taskExecutionId>
               <description>Calc LIVE BROKER margin : Account WebServiceTest_Account2(436) : Business Date (12-Feb-2007)</description>
            </TaskExecutionSubmitInfo>
         </SubmitMultipleCalcMarginRequestResult>
      </SubmitMultipleCalcMarginRequestResponse>
   </soap:Body>
</soap:Envelope>

And have been using the below to extract info from the nodes:

//*[name() = 'taskExecutionId']

Which returns:

<?xml version="1.0" encoding="UTF-8"?>

<root xmlns="http://XXX.com/optima/webservices">
  <taskExecutionId>74457</taskExecutionId>
  <taskExecutionId>74458</taskExecutionId>
</root>

But what can I do if I want to return just the second taskExecutionId? Or the first? I have tried appending with a [n] but this doesn’t to work. Any ideas?

Answer 1

To get the the N th instance of something in the whole XML document, you can use this XPath:

(//*[name() = 'taskExecutionId'])[N]

The parentheses are necessary. Without them, you’d be selecting the N th taskExecutionId under its particular parent.