Adds data to be passed in a SOAP request. For a web service, the data
are the method parameters.
payload
Returns a built SOAP request as a string.
Example
// Create a request to a web service "ws.strikeiron.com/relauto/iplookup/DNS"
$request = new CSOAPRequest( "DNSLookup", "http://tempuri.org/");
$request->addSOAPHeader( "LicenseInfo xmlns=\"http://ws.strikeiron.com\"",
array("UnregisteredUser" => array( "EmailAddress" => "qwerty@mail.ru" ))
);
$request->addParameter("server", "www.yandex.ru");