Passing XML to SOAP

[vertmonkee]

I am working with a web service which is expecting some XML.

If I do the following

$xml_file = file_get_contents('dataset.xml');

$params->xml = $xml_file;

$result = $client->Validation($params);

I get the following response

stdClass Object ( [ValidationResult] => stdClass Object ( [any] => Object reference not set to an instance of an object.  ) ) 

What is the correct way to pass the xml to the soap function?

Thanks