nullable types and the wsdl generated by Studio 2005

[Andy Babiec]

Assume I have the following web method...
[WebMethod(Description="Get rows from xyz filtered by the ParentID
column.")]
public xyzStructure StructureProvider_GetByParentID(System.Int32?
parentID, int start, int pageLength)
{
return StructureProvider.GetByParentID(parentID, start, pageLength);
}

(Note the Int32? data type - we want the user to be able to pass in a
null parentID)

Studio 2005 generates the following in the wsdl...
<s:element name="StructureProvider_GetByParentID">
<s:complexType>
<s:sequence>
<s:element minOccurs="1" maxOccurs="1" name="parentID"
nillable="true" type="s:int" />
<s:element minOccurs="1" maxOccurs="1" name="start" type="s:int" />
<s:element minOccurs="1" maxOccurs="1" name="pageLength" type="s:int"
/>
</s:sequence>
</s:complexType>
</s:element>
Is this correct? Can an xsd element be nillable="true" AND
minOccurs="1" ? The biztalk 2006 beta forum guys say this shouldn't be
allowed (since it doesn't like the example above)

[Josh Twist]

Yes, it basically means the element must be provided but it can be null
so it goes across the wire like this:

<parentID xsi:nil="true" />

You can achieve the same with standard reference types by decorating
them with [XmlElement(IsNullable=true)].

This can be useful for creating non-ambiguous WSDL when you have
<xs:any> placeholders.

Josh
http://www.thejoyofcode.com/