1 space node returns as empty

[David Thielen]

Hi;

This code is in J# so it looks a little weird but you could change it to C#
in a couple of seconds.

The problem here is a single space node returns as an empty node:

public static void main(String[] args) throws Exception
{

XmlDocument doc = new XmlDocument();
doc.set_Preserv eWhitespace(tru e);

String xml = "<root><spa ce> </space></root>";
Encoding encoder = Encoding.GetEnc oding("utf-8");
doc.Load(new MemoryStream(en coder.GetBytes( xml)));

XPathNavigator nav = new XPathDocument(n ew
XmlNodeReader(d oc)).CreateNavi gator();
nav = nav.SelectSingl eNode("/root");
nav = nav.SelectSingl eNode("./space");
String str = nav.get_Value() ;
int len = str.length();
System.out.prin tln("value = {" + str + "}");
System.out.prin tln("length = " + len);
}

Any ideas how to get back the space that is the node value? I tried
doc.set_Preserv eWhitespace(tru e); both before and after the Load.
--
thanks - dave

[Kevin Yu [MSFT]]

Hi dave,

I don't quite understand the code. Does XpathNavigator has a method named
SelectSingleNod e?

Kevin Yu
=======
"This posting is provided "AS IS" with no warranties, and confers no
rights."

[David Thielen]

Hello;

Yes, new to .net 2.0.

http://msdn2.microsoft.com/en-us/library/5htcxk90

--
thanks - dave
"Kevin Yu [MSFT]" wrote:

Hi dave,

I don't quite understand the code. Does XpathNavigator has a method named
SelectSingleNod e?

Kevin Yu
=======
"This posting is provided "AS IS" with no warranties, and confers no
rights."

[Martin Honnen]

David Thielen wrote:

The problem here is a single space node returns as an empty node:

public static void main(String[] args) throws Exception
{

XmlDocument doc = new XmlDocument();
doc.set_Preserv eWhitespace(tru e);

String xml = "<root><spa ce> </space></root>";
Encoding encoder = Encoding.GetEnc oding("utf-8");
doc.Load(new MemoryStream(en coder.GetBytes( xml)));

XPathNavigator nav = new XPathDocument(n ew
XmlNodeReader(d oc)).CreateNavi gator();
nav = nav.SelectSingl eNode("/root");
nav = nav.SelectSingl eNode("./space");
String str = nav.get_Value() ;
int len = str.length();
System.out.prin tln("value = {" + str + "}");
System.out.prin tln("length = " + len);
}

When I try the following C#

string xmlMarkup = "<root><tex t> </text></root>";

XmlDocument xmlDocument = new XmlDocument();
xmlDocument.Pre serveWhitespace = true;
xmlDocument.Loa dXml(xmlMarkup) ;

XmlElement text = xmlDocument.Sel ectSingleNode(@ "/root/text") as
XmlElement;
if (text != null) {
Console.WriteLi ne("InnerText: '{0}', Length: {1}.",
text.InnerText, text.InnerText. Length);

XPathNavigator xPathNavigator = text.CreateNavi gator();
Console.WriteLi ne("Value: '{0}', Length: {1}",
xPathNavigator. Value, xPathNavigator. Value.Length);
}

with .NET 2.0 Beta 2 I get the output

InnerText: ' ', Length: 1.
Value: ' ', Length: 1

which seems fine to me, so maybe you can streamline your code.

Or do you have specific needs to
- create a memory stream from a string
- load an XmlDocument from that memory stream
- create a XmlNodeReader on that XmlDocument
- create an XPathDocument on that XmlNodeReader
- create an XPathNavigator from the XPathDocument
when loadXml exists for the first two steps and the XPathNavigator can
simply be created from an XmlNode?
--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/

[David Thielen]

Hi;

Interesting - I tried that and got that too (J#):
XmlElement elem = (XmlElement)doc .SelectSingleNo de("/root/space");
String str = elem.get_InnerT ext(); // get a 1 space string

XPathNavigator nav = new XPathDocument(n ew
XmlNodeReader(d oc)).CreateNavi gator();
nav = nav.SelectSingl eNode("/root/space");
String str = nav.get_Value() ; // a 0 length string

Does XPathDocument just never allow whitespace? I hate to not be able to use
it as it is the recomended API and a lot faster. But I have to get the actual
node contents.

--
thanks - dave
"Martin Honnen" wrote:

David Thielen wrote:

The problem here is a single space node returns as an empty node:

public static void main(String[] args) throws Exception
{

XmlDocument doc = new XmlDocument();
doc.set_Preserv eWhitespace(tru e);

String xml = "<root><spa ce> </space></root>";
Encoding encoder = Encoding.GetEnc oding("utf-8");
doc.Load(new MemoryStream(en coder.GetBytes( xml)));

XPathNavigator nav = new XPathDocument(n ew
XmlNodeReader(d oc)).CreateNavi gator();
nav = nav.SelectSingl eNode("/root");
nav = nav.SelectSingl eNode("./space");
String str = nav.get_Value() ;
int len = str.length();
System.out.prin tln("value = {" + str + "}");
System.out.prin tln("length = " + len);
}

When I try the following C#

string xmlMarkup = "<root><tex t> </text></root>";

XmlDocument xmlDocument = new XmlDocument();
xmlDocument.Pre serveWhitespace = true;
xmlDocument.Loa dXml(xmlMarkup) ;

XmlElement text = xmlDocument.Sel ectSingleNode(@ "/root/text") as
XmlElement;
if (text != null) {
Console.WriteLi ne("InnerText: '{0}', Length: {1}.",
text.InnerText, text.InnerText. Length);

XPathNavigator xPathNavigator = text.CreateNavi gator();
Console.WriteLi ne("Value: '{0}', Length: {1}",
xPathNavigator. Value, xPathNavigator. Value.Length);
}

with .NET 2.0 Beta 2 I get the output

InnerText: ' ', Length: 1.
Value: ' ', Length: 1

which seems fine to me, so maybe you can streamline your code.

Or do you have specific needs to
- create a memory stream from a string
- load an XmlDocument from that memory stream
- create a XmlNodeReader on that XmlDocument
- create an XPathDocument on that XmlNodeReader
- create an XPathNavigator from the XPathDocument
when loadXml exists for the first two steps and the XPathNavigator can
simply be created from an XmlNode?
--

Martin Honnen --- MVP XML
http://JavaScript.FAQTs.com/

[Oleg Tkachenko [MVP]]

David Thielen wrote:

Any ideas how to get back the space that is the node value? I tried
doc.set_Preserv eWhitespace(tru e); both before and after the Load.

When loading XPathDocument you have to preserve whitespace, by default
it's not preserved.
XPathNavigator nav = new XPathDocument(n ew
XmlNodeReader(d oc), XmlSpace.Preser ve).CreateNavig ator();

--
Oleg Tkachenko [XML MVP, MCAD]
http://www.xmllab.net
http://blog.tkachenko.com

[Oleg Tkachenko [MVP]]

David Thielen wrote:

Does XPathDocument just never allow whitespace? I hate to not be able to use
it as it is the recomended API and a lot faster. But I have to get the actual
node contents.

Second argument to XPathDocument is supposed to control whitespace
handling. By default it's XmlSpace.Defaul t, which doesn't preserve
insignificant whitespace (whitespace-only text between tags).
--
Oleg Tkachenko [XML MVP, MCAD]
http://www.xmllab.net
http://blog.tkachenko.com

[David Thielen]

Bingo - that's it.

I never looked at that ctor because I was using the XPathDocument(S tream)
ctor. But doing it as you suggest below works & slips right in.

--
thanks - dave
"Oleg Tkachenko [MVP]" wrote:

David Thielen wrote:

Any ideas how to get back the space that is the node value? I tried
doc.set_Preserv eWhitespace(tru e); both before and after the Load.

When loading XPathDocument you have to preserve whitespace, by default
it's not preserved.
XPathNavigator nav = new XPathDocument(n ew
XmlNodeReader(d oc), XmlSpace.Preser ve).CreateNavig ator();

--
Oleg Tkachenko [XML MVP, MCAD]
http://www.xmllab.net
http://blog.tkachenko.com