Traversing XML tree - but how do I get the leafs only?

[Christian Rühl]

Good Day, folks!

I'm having a problem traversing an XmlDocument tree in C#. I only want
to access the InnerText of the leafs and the names of their ancestors
and show them in a richTextBox. But if I go like this I get the
InnerText of all the nodes and the outcome in my richTextBox is just a
mess.

The XML files i want to handle here have about 2300 nodes, so that
accessing some nodes directly is just impossible.

Can anyone help me here? Thanks!

BTW: What is this CreateNavigator() thing doing? I just found that
somewhere but haven't found out what I can do with it yet.

/// <summary>
/// writes collected data to page
/// </summary>
public void printPage(XmlDocument dom)
{
richTextBox1.Text = null;

// node-tree root
XmlNode root = dom.DocumentElement;

//nodeRead = new XmlNodeReader(dom);
//nav = dom.CreateNavigator();

// SELECT statement
XmlNodeList nodeList;
nodeList = root.SelectNodes("/descendant::*");

MessageBox.Show(Convert.ToString(nodeList.Count));

// traverse the node-tree
if(dom.HasChildNodes)
{
foreach(XmlNode myNode in nodeList)
{
richTextBox1.Text = richTextBox1.Text
+ Convert.ToString(myNode.Name) + ": "
/*+ Convert.ToString(myNode.InnerText)*/
+ "\n\n";
}
}
}

[Martin Honnen]

Christian Rühl wrote:

I'm having a problem traversing an XmlDocument tree in C#. I only want
to access the InnerText of the leafs and the names of their ancestors
and show them in a richTextBox. But if I go like this I get the
InnerText of all the nodes and the outcome in my richTextBox is just a
mess.

public void printPage(XmlDocument dom)
{
richTextBox1.Text = null;

XmlNodeList nodeList;
nodeList = root.SelectNodes("/descendant::*");

Use
XmlNodeList nodeList = dom.SelectNodes("//*[not(*) and text()]");
foreach (XmlElement element in nodeList) {
// use e.g. element.InnerText, element.Name
}
That way you process all elements that have no elements as child nodes
but have text child nodes.

The real leaf nodes however are the text nodes so depending on your
needs you might want
XmlNodeList nodeList = dom.SelectNodes("//text()");
and loop through those text nodes.
--

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

[Christian Rühl]

cool, cool! thank you martin! that was exactly what i was looking for!
thanks!!!

[Christian Rühl]

okay guy, here's another question for you now:

i built an iterator to get all the nodes with a certain attribute in an
xml dom. this all looks like this:

string xpath;

// iterate over all xmlnodes with attribute "status='checked'"
XPathDocument xpathDoc = new XPathDocument(m_configFile);
XPathNavigator xpathNav = xpathDoc.CreateNavigator();
XPathNodeIterator nodeIter = xpathNav.Select(@"/*[@status='checked']");

while(nodeIter.MoveNext())
{
xpath = nodeIter.CurrentPosition.ToString();
// here i want to address an treeview node with the xpath to set its
checkbox
}

so, how can i address a treeview node with a path? for if i go like
treeView1.SelectedNode it randomly choses a node in treeView control.

i'm using .NET framework 1.1.

[Christian Rühl]

hello!

i hope qou can help me with another problem i have.
what i want to do is simple: i have an xpath of a node that not yet
exists and i want to create that node in my config.xml file.

to do this, i split up the xpath into parts and check if a
correspondent node exists by putting fragment by fragment together
until i hit a part of my path that does not exist.

if i suffer such an event, i want to add a child node to the existing
parent node and so on... i don't get errors, but somehow this doesn't
work. can anybody help me out? i am really grounded now... i absolutly
no idea how to solve this. i have a feeling, that i'm pretty close now,
but i can't do the last steps...

thanks in advance!

/// <summary>
/// add child nodes by xpath
/// </summary>
private XmlNode AddNodeByXpath(string xpath, XmlDocument dom)
{
XmlNode node;
XmlNode parent;

string[] tempXpath = null; // empty array
char separator = Convert.ToChar("/"); // separator sign

string temp = null; // empty temp node
string oldTemp = null;
int i = 1; // split index

try
{
node = dom.SelectSingleNode(xpath);

// Get a XML node type object.
Type XmlNodeType = typeof(XmlNode);

// split xpath into parts
tempXpath = xpath.Split(separator);

// set temp node = root
temp = tempXpath[0];
oldTemp = temp;

// node checked and correspondent xml node found?
while(i<tempXpath.Length)
{
node = dom.SelectSingleNode(temp);
parent = dom.SelectSingleNode(oldTemp);

if(XmlNodeType.IsInstanceOfType(node))
{
// if node exists, check for child node
oldTemp = temp;
temp = temp + "/" + tempXpath[i];
}
else
{
//node = dom.CreateElement(tempXpath[i]);
// if node does not exist, append node
parent.AppendChild(dom.CreateElement(tempXpath[i]));
}

// perform step
i++;
}
return node;
}
catch(Exception ex)
{
MessageBox.Show(ex.Message);
return null;
}
}