Creating a SOAP message for SharePoint Web Services

I try to create a request for a SharePoint web service.

I added a Web Reference based on the SharePoint Web service.

Request messages are based on a multi-part
Message Type and each part is a .Net primitive.

In order to create the message I use a Message Assignement.

Everything works well as long there is no parameters (An empty  Construct Message shape does the work) or when parts are of type string:

MyMessage.myStringPart = “SomeString”;

Problems occurs when the primitive is XmlDocument.

– If no part definition => does not not compile, error “Message part has not been initialized”

– If MyMessage.myXmlDocumentPart = null; => Error: “The part … of message … contained a null value at the end of the construct block”

I also tried to define xmlDoc as a variable of type XmlDocument, use xmlDoc.LoadXML(something) and MyMessage.myXmlDocumentPart = xmlDoc:

If …

– xmlDoc.LoadXml(“”); => Error “the part contains zero bytes of data”

– xmlDoc.LoadXml(“<value/>”); => SharePoint SoapServerException

– xmlDoc.LoadXml(“<soap:query></soap:query>”); => Error about soap namespace (don’t remember the exact message)

– xmlDoc.LoadXml(“<ns0:query xmlns:ns0=’http://schemas.microsoft.com/sharepoint/soap/’><Value/></ns0:query>&#8221;); => SharePoint SoapServerException

So, what should I try ?