Web Services Quiz: Issue 4 - the Answer
The answer to quiz 4 is quite surprising:
<s:complexType name="AddRequestMsg">
<s:sequence>
<s:element minOccurs="1" maxOccurs="1" name="a" type="s:int" />
<s:element minOccurs="1" maxOccurs="1" name="b" type="s:int" />
</s:sequence>
</s:complexType>
And this, although the CLR type obviously tells the XML-serializer to generate attributes instead of elements:
public class AddRequestMsg
{
[XmlAttribute]
public int a;
[XmlAttribute]
public int b;
}
Note, this is not a bug, it’s a feature: The described Web Method uses the section 5 encoding style by applying the [SoapRpcMethod] attribute. Well, by definition, this encoding doesn’t support attributes. Therefore XML elements get generated although [XmlAttribute] has been specified.
Removing the [SoapRpcMethod] and we get the expected schema:
<s:complexType name="AddRequestMsg">
<s:attribute name="a" type="s:int" use="required" />
<s:attribute name="b" type="s:int" use="required" />
</s:complexType>
Now thinking the other way round: What happens if a section 5 encoding Web Service refers to a XML schema that contains XML attributes?
Answer: It’s simply not valid.