Deserialize from SelectSingleNod e

[Geoff]

Is it possible to pull a single node (element) out of a complex XML
file, using SelectSingleNod e(), and then deserialize that node to an
object?

Could someone please post, or point me to, a simple, but complete
example?

[Derek Harmon]

"Geoff" <ge*********@gm ail.com> wrote in message news:db******** *************** ***@posting.goo gle.com...

Is it possible to pull a single node (element) out of a complex XML
file, using SelectSingleNod e(), and then deserialize that node to an
object?

Yes, if your XML document looks like this, for example,

<MyDocument>
<ComplexInfo>
<DontCare SomeStatistic=" 55" />
</ComplexInfo>
<MyObject>
<Name>Geoff</Name>
</MyObject>
</MyDocument>

and you have a class to deserialize that looks like this,

public class MyObject
{
public string Name;
}

then you should have no problem selecting a single node, MyObject,
from the more complex document and then wrapping that node in an
XmlNodeReader to use for deserialization , like this,

XmlSerializer serializer = new XmlSerializer( typeof( MyObject));
XmlDocument doc = new XmlDocument( );
doc.Load( "myDocument.xml ");

XmlNode node = doc.SelectSingl eNode( "//MyObject");
MyObject obj = serializer.Dese rialize( new XmlNodeReader( node)) as MyObject;
Derek Harmon

[Geoff]

Derek, thank you so much for the excellent response. You are a
gentleman and a scholar. You have confirmed for me that my approach
should work, but I'm still having trouble, I think because of
namespaces declared in the XML file. Can you expand your example a
bit to account for a default namespace in the XML file? Or, can you
tell me what might be wrong with my code, below?

The "deserializ e" statement gives me the following error:

There is an error in the XML document. --> &lt;FIELDED_ADD RESS
xmlns='http://www.telcordia.c om/IDN/ELMS6'&gt; was not expected.

"FIELDED_ADDRES S" is the name of the node I'm trying to
select/deserialize.

"http://www.telcordia.c om/IDN/ELMS6" is a namespace declared in the
XML file.

My code looks like this:

XmlDocument ResponseDocumen t = new XmlDocument();
ResponseDocumen t.Load @"C:\MyFile.xml ");
NamespaceManage r = new
XmlNamespaceMan ager(ResponseDo cument.NameTabl e);
NamespaceManage r.AddNamespace( "p",
"http://www.telcordia.c om/IDN/ELMS6");
XPathQuery = @"//p:FIELDED_ADDRE SS";
XmlNode AddressNode = ResponseDocumen t.SelectSingleN ode(XPathQuery,
NamespaceManage r);
if (AddressNode != null)
{
ALTERNATIVE_ADD RESSFIELDED_ADD RESS FieldedAddress;
XmlNodeReader NodeReader = new XmlNodeReader(A ddressNode);
XmlSerializer Serializer = new
XmlSerializer(t ypeof(ALTERNATI VE_ADDRESSFIELD ED_ADDRESS),
"http://www.telcordia.c om/IDN/ELMS6");
FieldedAddress = Serializer.Dese rialize(NodeRea der) as
ALTERNATIVE_ADD RESSFIELDED_ADD RESS;
}

My XML file looks like this:

<?xml version="1.0" ?>
<Signature xmlns="http://www.w3.org/2000/09/xmldsig#">
<Object Id="pp">
<ADDRESS_VALIDA TION_OUTPUT
xmlns:xsi="http ://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.telcordia.c om/IDN/ELMS6"
version="ELMS6_ ADDRESS_VALIDAT ION_OUTPUT_v2-0"
xsi:schemaLocat ion="http://www.telcordia.c om/IDN/ELMS6
ADDRESS_VALIDAT ION_OUTPUT.xsd" >
<COMMON_QUERY_R SP></COMMON_QUERY_RS P>
<ALTERNATIVE_AD DRESS_INFORMATI ON_LIST>
<ALTERNATIVE_AD DRESS_INFORMATI ON>
<ALTERNATIVE_AD DRESS>
<FIELDED_ADDRES S>
<SANO>1445</SANO>
<SATH>DR</SATH>
<SASN>MONROE</SASN>
<SASS>NE</SASS>
<LD3>APT</LD3>
<LV3>C-27</LV3>
<CITY>ATLANTA </CITY>
<STATE>GA</STATE>
</FIELDED_ADDRESS >
</ALTERNATIVE_ADD RESS>
</ALTERNATIVE_ADD RESS_INFORMATIO N>
</ALTERNATIVE_ADD RESS_INFORMATIO N_LIST>
</ADDRESS_VALIDAT ION_OUTPUT>
</Object>
</Signature>

[Geoff]

OK. I got this working finally! Cool. Thank you.

The Serializer.Dese rialize() method kept giving me "XXX was not
expected."

I thought it was talking about the namespace for XXX, but it was
actually complaining about the entire element. Why?... Apparently
because my class name didn't exactly match the element in the XML
file.

Unfortunately, my class name was generated from an XSD file for the
XML file I'm working with. The class name has the form AAABBBCCC,
where the actual element I'm interested in, CCC, is nested under
elements AAA and BBB. I really don't want to change it, to match the
element, because if the XSD changes in the future, I will use the
xsd.exe tool to regenerate the classes, and any manual changes I've
made will get blasted.

Maybe there is an option for xsd.exe to generate class names which
match the element names, or maybe there is a way to do the
Deserialize() without the names matching. ???

[Geoff]

I was able to use the XmlRoot attribute to map the class name to the
element name in the XML file, so at least now I won't have to actually
change the xsd.exe generated classes themselves. Only issue now is
I'll have to add the attribute any time the XSD file changes. Not
such a big deal. Example below:
[System.Xml.Seri alization.XmlTy peAttribute(Nam espace="http://www.telcordia.c om/IDN/ELMS6")]

[XmlRoot (ElementName="F IELDED_ADDRESS" )]

public class ADDRESS_VALIDAT ION_OUTPUTALTER NATIVE_ADDRESS_ INFORMATIONALTE RNATIVE_ADDRESS FIELDED_ADDRESS

[William Stacey [MVP]]

Thanks Derek. Just curious if Deserializing the whole thing with
XmlSerializer to get the MyObject string and using that to deserialize the
string xml would be faster or slower? Naturally you would need to define
MyDocument in a class first. Does not XmlDocument deserializing the whole
thing also just to find the MyObject tag? TIA

--
William Stacey, MVP
http://mvp.support.microsoft.com

"Derek Harmon" <lo*******@msn. com> wrote in message
news:OH******** *****@TK2MSFTNG P11.phx.gbl...

"Geoff" <ge*********@gm ail.com> wrote in message news:db******** *************** ***@posting.goo gle.com...

Is it possible to pull a single node (element) out of a complex XML
file, using SelectSingleNod e(), and then deserialize that node to an
object?

Yes, if your XML document looks like this, for example,

<MyDocument>
<ComplexInfo>
<DontCare SomeStatistic=" 55" />
</ComplexInfo>
<MyObject>
<Name>Geoff</Name>
</MyObject>
</MyDocument>

and you have a class to deserialize that looks like this,

public class MyObject
{
public string Name;
}

then you should have no problem selecting a single node, MyObject,
from the more complex document and then wrapping that node in an
XmlNodeReader to use for deserialization , like this,

XmlSerializer serializer = new XmlSerializer( typeof( MyObject));
XmlDocument doc = new XmlDocument( );
doc.Load( "myDocument.xml ");

XmlNode node = doc.SelectSingl eNode( "//MyObject");
MyObject obj = serializer.Dese rialize( new XmlNodeReader( node)) as

MyObject;

Derek Harmon