XML Question

[Michael C]

Hi all,

Please excuse all the questions... I come from a VB 6 background and am
trying to teach myself C#.NET. I appreciate all your help. My question now
is this -- I have a simple XML file like this:

<?xml version='1.0'?>
<enterprise>
<config>
<load value1="10" value2="14" />
</config>
<servers>
<server name="sqlsrv1" username="" pwd="" integratedsec="yes">
<server name="sqlsrv2" username="sa" pwd="sa" integratedsec="no">
</servers>
</enterprise>

I'm able to read in the information using an XmlTextReader, and when I
update the information I have to re-write the entire file again from
scratch. Just looking at my code I gotta believe there's an easier way...
as it stands I'd be better off with a plain text file . Can someone point
me in the right direction for info on efficient uses of the System.Xml
namespace (for instance, to extract certain tags and their attributes or to
add/modify tags or their attributes)? So far I've gone through Microsoft's
examples but I'm still not getting it. Thanks!

Michael C.

 

[clintonG]

I'm getting something from this book [1] from O'Reilly.
I also highly recommend any of the QUE MCAD Training Guides
authored by Amit Kahlani.

--
<%= Clinton Gallagher
A/E/C Consulting, Web Design, e-Commerce Software Development
Wauwatosa, Milwaukee County, Wisconsin USA
NET csgallagher@ REMOVETHISTEXT metromilwaukee.com
URL http://www.metromilwaukee.com/clintongallagher/


[1]
http://www.amazon.com/exec/obidos/tg/detail/-/0596003978/103-2141131-0802245?v=glance

 

[Mark Broadbent]

Hi Michael, nice to see someone similar to me on this ng (I am successfully
forgetting VB it is now just a distant nightmare)

Anyway, I am currently using book 0-7897-2824-9 (QUE Kalani) and so far I
can recommend it for this kind of thing (although doesnt look like you can
grab the code samples ..means typing for a change and actually doing the
exercises

Onto your problem, you are correct that using XmlTextReader you cant write
the elements attributes seperately.
You are also correct that there is an easier way - You need to open an
XmlDataDocument and from this document you can return a reference to a
XmlNode. Using this you can read write.

See this code snippet that I typed in yesterday (you can use it to see how
to use the XmlDataDocument object.

private void buttonReadXML_Click(object sender, System.EventArgs e)

{

XmlTextReader xtr = new XmlTextReader(@"..\..\Books.xml");

xtr.WhitespaceHandling = WhitespaceHandling.None;

XmlDocument xd = new XmlDocument();

xd.Load(xtr);

XmlNode xnodRoot = xd.DocumentElement;

XmlNode xnodWorking;

if (xnodRoot.HasChildNodes)

{

xnodWorking = xnodRoot.FirstChild;

while (xnodWorking != null)

{

addChildren(xnodWorking, 0);

xnodWorking = xnodWorking.NextSibling;

}

}

xtr.Close();

}

private void addChildren(XmlNode xnod, int depth)

{

StringBuilder sbNode = new StringBuilder();

if ( (xnod.NodeType == XmlNodeType.Element) || (xnod.NodeType ==
XmlNodeType.Text) )

{

sbNode.Length = 0;

for (int i = 1; i <= depth; i++)

{

sbNode.Append(" ");

}

sbNode.Append(xnod.Name + " ");

sbNode.Append(xnod.NodeType.ToString());

sbNode.Append(": " + xnod.Value);

this.listBoxNodes.Items.Add(sbNode.ToString());

XmlAttributeCollection atts = xnod.Attributes;

if (atts != null)

{

for (int i = 0; i < atts.Count; i++)

{

sbNode.Length = 0;

for (int j = 1; j <= depth + 1; j++)

{

sbNode.Append(" ");

}

sbNode.Append(atts.Name + " ");

sbNode.Append(atts.NodeType.ToString());

sbNode.Append(": " + atts.Value);

this.listBoxNodes.Items.Add(sbNode);

}

}

XmlNode xnodworking;

if (xnod.HasChildNodes)

{

xnodworking = xnod.FirstChild;

while (xnodworking != null)

{

addChildren( xnodworking, depth + 1);

xnodworking = xnodworking.NextSibling;

}

}

}

}



--


Br,
Mark Broadbent
mcdba , mcse+i
=============