How can i validate a SOAP message with a WSDL file?

when we receive a SOAP message, then we Resolve it, then we have a TEXT like:

<soap:Envelope>
        <soap:Body>
                <GetDNS>
                  <xx>1</xx>
                </GetDNS>
        </soap:Body>
</soap:Envelope>

how can i validate the para: xx . to check it's value is accord to the WSDL of the web service

Copyright Notice：Content Author:「Allen shen」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/2742164/how-can-i-validate-a-soap-message-with-a-wsdl-file