Hi...

I just noticed something that seems counter-intuitive to me. By default an
XmlDocument is set with PreserveWhitespace=false. This means that
XmlDocument.Load() or .LoadXml() will strip/condense non-semantic whitespace.

*But* I just found that if you take that self-same XmlDocument and do either
XmlDocumentFragment node = doc.CreateDocumentFragment();
node.InnerXml = "<foo/>\r\n<bar/>";

or
XmlElement node = doc.CreateElement("baz");
node.InnerXml = "<foo/>\r\n<bar/>";

that the whitespace gets preserved, despite the parent document settings.

What's the rationale for this?

Thanks
Mark

Mark wrote:

> I just noticed something that seems counter-intuitive to me. By default an
> XmlDocument is set with PreserveWhitespace=false. This means that
> XmlDocument.Load() or .LoadXml() will strip/condense non-semantic whitespace.
>
> *But* I just found that if you take that self-same XmlDocument and do either
> XmlDocumentFragment node = doc.CreateDocumentFragment();
> node.InnerXml = "<foo/>\r\n<bar/>";
>
> or
> XmlElement node = doc.CreateElement("baz");
> node.InnerXml = "<foo/>\r\n<bar/>";
>
> that the whitespace gets preserved, despite the parent document settings.
>
> What's the rationale for this?

I am not sure but OuterXml/InnerXml never pay attention to the
PreserveWhitespace property, neither on reading nor on setting.

Here is an example showing that for reading OuterXml and comparing it to
the Save method:

XmlDocument doc = new XmlDocument();
doc.LoadXml("<root><foo><bar>baz</bar></foo></root >");
doc.Save(Console.Out);
Console.WriteLine();
Console.WriteLine(doc.OuterXml);
doc.PreserveWhitespace = true;
doc.Save(Console.Out);
Console.WriteLine();
Console.WriteLine(doc.OuterXml);

Output is

<?xml version="1.0" encoding="ibm850"?>
<root>
<foo>
<bar>baz</bar>
</foo>
</root>
<root><foo><bar>baz</bar></foo></root>
<?xml version="1.0"
encoding="ibm850"?><root><foo><bar>baz</bar></foo> </root>
<root><foo><bar>baz</bar></foo></root>



--

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

Thanks for the reply, Martin...

The interesting wrinkle in your sample is that .Save() actually injects
whitespace when PreserveWhitespace = false. The original string you parsed
had no non-semantic whitespace in it, yet the first .Save() applied
formatting to add some.

My next experiment was going to try making an XmlTextReader using
XmlParserContext to see how that interacted with whitespace...

Mark


"Martin Honnen" wrote:

> Mark wrote:
>
> > I just noticed something that seems counter-intuitive to me. By default an
> > XmlDocument is set with PreserveWhitespace=false. This means that
> > XmlDocument.Load() or .LoadXml() will strip/condense non-semantic whitespace.
> >
> > *But* I just found that if you take that self-same XmlDocument and do either
> > XmlDocumentFragment node = doc.CreateDocumentFragment();
> > node.InnerXml = "<foo/>\r\n<bar/>";
> >
> > or
> > XmlElement node = doc.CreateElement("baz");
> > node.InnerXml = "<foo/>\r\n<bar/>";
> >
> > that the whitespace gets preserved, despite the parent document settings.
> >
> > What's the rationale for this?
>
> I am not sure but OuterXml/InnerXml never pay attention to the
> PreserveWhitespace property, neither on reading nor on setting.
>
> Here is an example showing that for reading OuterXml and comparing it to
> the Save method:
>
> XmlDocument doc = new XmlDocument();
> doc.LoadXml("<root><foo><bar>baz</bar></foo></root >");
> doc.Save(Console.Out);
> Console.WriteLine();
> Console.WriteLine(doc.OuterXml);
> doc.PreserveWhitespace = true;
> doc.Save(Console.Out);
> Console.WriteLine();
> Console.WriteLine(doc.OuterXml);
>
> Output is
>
> <?xml version="1.0" encoding="ibm850"?>
> <root>
> <foo>
> <bar>baz</bar>
> </foo>
> </root>
> <root><foo><bar>baz</bar></foo></root>
> <?xml version="1.0"
> encoding="ibm850"?><root><foo><bar>baz</bar></foo> </root>
> <root><foo><bar>baz</bar></foo></root>
>
>
>
> --
>
> Martin Honnen --- MVP XML
> http://JavaScript.FAQTs.com/
>