Iterate through XDocument when you dont know the structure - c#

Is there any way to iterate through a XDocument when you dont know what the XML structure is (using c#)?
There is plenty of examples when you know the structure, like the answer to this question : C# - Select XML Descendants with Linq and C# Foreach XML Node
I've tried Descendants("A") where A is the example below - which in my foreach returns me one element with the name as the root and the value as 'all of the values concatinated into one string'
The reason I'm doing this is to anonymize certain nodes which I know the names.
The XDocument's I'm loading can be of any shape - so i've decided to just create a list which users can add to which contains these sensitive elements.
A solution I want to avoid is users creating XPath's for sensitive fields.
The XML is also sensitive so I cant share online literally but one example (out of 5) would look.
<A>
<B>
<C>
<D>
<dee>value1</dee>
<doo>value2</doo>
<date>value3</date>
<time>value4</time>
</D>
</C>
</B>
<E>
...ommited..this doc is 5000 lines long with 500~ unique node names
</E>
............
</A>
So is there a way to iterate without using Descendants?

Use .Descendants() to iterate every element.
xmlDoc.Root.Descendants()
.ToList()
.ForEach(e => Console.WriteLine(e.Name));

This is the way I went about it.
Descendants means you know the structure of the nodes before hand. Even with an empty method call to descendants (which should get everything from the root) wasn't giving me what I was expecting.
The below code should work for any XML document, without knowing the structure.
XmlDocument doc = new XmlDocument();
doc.Load(file);
using (XmlReader reader = new XmlNodeReader(doc))
{
while (reader.Read())
{
currentNodeName = reader.Name;

Related

Query XDocument based on the depth of the node

I have the following XML and I want to be able to query the XML based on the depth of it. I am aware of the depth before hand.
UPDATED QUESTION:
I have the following XML and I want to be able to query the XML based on if the nodes are repetitive.
So, this is my XML
<Books>
<BookID>12345</BookID>
<BookName>BookName</BookName>
<Authors>
<Author>
<Name>AuthorNameOne</Name>
<City>New York</City>
</Author>
<Author>
<Name>AuthorNameTwo</Name>
<City>New York</City>
</Author>
</Authors>
</Books>
Via XDocument I want to be able to query this XML and get node names for the elements where there is repetitive data such as Authors. Or I want to be able to query it based on the Depth of the Node.
UPDATED QUESTION:
Via XDocument I want to be able to query this XML and get node names for the elements where there is repetitive data such as Authors.
Any help will be much appreciated.
Your XML still doesn't really make sense, but I'm putting together this answer hoping that it will at least point you in the right direction. I'm going to completely ignore the portion of your question that references node depth because I'm not really sure how it applies to the following question that you posted:
Via XDocument I want to be able to query this XML and get node names for the elements where there is repetitive data such as Authors.
Here's how to do just that simple type query assuming that your XDocument is named xml:
List<XElement> repeatedNodes = new List<XElement>();
for(XElement node in xml.Descendants())
{
if(node.Parent.Elements(node.Name).Count() > 1))
{
repeatedNodes.Add(node);
}
}
Here's the same code compressed into a lambda that will provide you with an IEnumerable<XElement> containing all of the elements that would go into the List in my first example:
var dupes = xml.Descandants().Where(n => n.Parent.Elements(n.Name).Count() > 1);
This algorithm will look at every node in the xml tree and then from the parent of the current node it will count how many nodes with that same name exist. If that number is greater than one it will add it to our list of repeated nodes. This does not care what depth the current node is and it will only count duplicate named nodes at the same depth. Additionally this algorithm will put dupes in the List structure, but you can add in your own logic to prevent it from doing that or use a different structure that doesn't allow duplicates.

Saving "skipped" nodes in xml into array

In my code, I am downloading an xml file, and because one of the nodes is variable (both name and count of them), I use code like this:
XmlNodeList arrivals = airplanes.SelectNodes("/myXml/flights/*/arrivals");
Now what I need to do, is saving names of the nodes skipped by "*" into an array, or arraylist, something like that. Later I will need to use some foreach to do something with each of the nodes, now saved as strings. I have tried
foreach(* in MyArrayList)
and that doesnt work, I get a number of errors there, assuming I cant use the " * " here.
Each XmlNode in the XmlNodeList has a ParentNode property, you should be able to use that to navigate back up from the arrivals node in the xml to the * node.
The following Linq query should get the names:
var names = arrivals.Cast<XmlNode>().Select(x => x.ParentNode.Name).ToList();
The Cast<XmlNode> is needed because XmlNodeList doesn't implement the generic IEnumerable interface.

Get specific data from XML document

I have xml document like this:
<level1>
<level2>
<level3>
<attribute1>...</attribute1>
<attribute2>false</attribute2>
<attribute3>...</attribute3>
</level3>
<level3>
<attribute1>...</attribute1>
<attribute2>true</attribute2>
<attribute3>...</attribute3>
</level3>
</level2>
<level2>
<level3>
<attribute1>...</attribute1>
<attribute2>false</attribute2>
...
...
...
I'm using c#, and I want to go thru all "level3", and for every "level3", i want to read attribute2, and if it says "true", i want to print the corresponding attribute3 (can be "level3" without these attributes).
I keep the xml in XmlDocument.
Then I keep all the "level3" nodes like this:
XmlNodeList xnList = document.SelectNodes(String.Format("/level1/level2/level3"));
(document is the XmlDocument).
But from now on, I don't know exactly how to continue. I tried going thru xnList with for..each, but nothing works fine for me..
How can I do it?
Thanks a lot
Well I'd use LINQ to XML:
var results = from level3 in doc.Descendants("level3")
where (bool) level3.Element("attribute2")
select level3.Element("attribute3").Value;
foreach (string result in results)
{
Console.WriteLine(result);
}
LINQ to XML makes all kinds of things much simpler than the XmlDocument API. Of course, the downside is that it requires .NET 3.5...
(By the way, naming elements attributeN is a bit confusing... one would expect attribute to refer to an actual XML attribute...)
You can use LINQ to XML and reading this is a good start.
You can use an XPath query. This will give you a XmlNodeList that contains all <attribute3> elements that match your requirement:
var list = document.SelectNodes("//level3[attribute2 = 'true']/attribute3");
foreach(XmlNode node in list)
{
Console.WriteLine(node.InnerText);
}
You can split the above xpath query in three parts:
"//level3" queries for all descendant elements named <level3>.
"[attribute2 = 'true']" filters the result from (1) and only keeps the elements where the child element <attribute2> contains the text true.
"/attribute3" takes the <attribute3> childnode of each element in the result of (2).

How to get the immediate child elements of the root element using C# and XML?

<Document>
<Heading1>
<text>Heading Title</text>
<para>para1</para>
<para>para2</para>
<para>para3</para>
</Heading1>
<Heading1>
<text>2nd Heading Title</text>
<para>para4</para>
<para>para5</para>
<para>para6</para>
<Heading2>
<text>3rd Heading Title</text>
<para>para4</para>
<para>para5</para>
</Heading2>
</Heading1>
</Document>
This is XML Document. Now, i want to parse this XML file using C# (4.0). Here, I want to get all the Heading1 elements without using that element name in my program. For example, don't use document.GetElementsByTagName("Heading1");. How i get it. Guide me get out of this issue.
Thanks & Regards.
Using LINQ to XML, you can do:
var headings = yourXDocument.Root.Elements();
Using Nodes() instead of Elements() will also return text nodes and comments, which is apparently not what you want.
You can access the child elements of the document or element through the Elements() method if using LINQ to XML.
XDocument doc = ...;
var query = doc.Root.Elements();
If you're using XmlDocument, this works:
var elements = doc.SelectNodes("/*/*");
That finds all child elements of the top-level element irrespective of any of their names. It's usually safer to specify the names if you know them, so that elements with unexpected names don't get returned in your list - use /Document/Heading1 to do this.

Read XMLDocument node without reading its child nodes in C#

Sample XML
<A>
<B>
<B1/>
<B2/>
<B3/>
<B4/>
<B5/>
</B>
<C>
<C1/>
<C2/>
<C3/>
<C4/>
<C5/>
</C>
</A>
Query:
C#
When I read the the child nodes of A it retuns nodes B & C with their child nodes.
Is there any possibility so that I can get only B & C without their respective child nodes
I need to populate the tree with this type of xml & the xml file is quite big. so I need to load the childs at the time of expanding any node
Requirement is
Suppose I try to expand A node the I want only B & C,
If I expand B then I want B1 to B5
Use a XmlReader. XmlDocument by design has to load the whole Xml document into memory.
if you use java, you can implement a SAX Handler building your DOM and ignoring the children.
It's a badly worded question so I'm not entirely sure what you are trying to do but if you just want all the child nodes of the root (A) then use an XmlDocument with XPath like this:
XmlDocument doc = new XmlDocument();
doc.Load(xmlFile);
XmlNodeList nodes = doc.SelectNodes("/A/*");
foreach(XmlNode node in nodes){
//DO STUFF
}
if i understand the question right, u need to get children of the node without getting their children. this can be done by xquery
(child::*)
so if u apply it in A node it will give B and C. if u apply it in B then it will give B1-B5.

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