Unit testing XML Generation [closed] - c#

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What unit testing strategies do people recommend for testing xml is being generated correctly.
The my current tests seem abit primitive, something along the lines of:
[Test]
public void pseudo_test()
{
XmlDocument myDOC = new XmlDocument();
mydoc = _task.MyMethodToMakeXMLDoc();
Assert.AreEqual(myDoc.OuterXML(),"big string of XML")
}

First, as pretty much everyone is saying, validate the XML if there's a schema defined for it. (If there's not, define one.)
But you can build tests that are a lot more granular than that by executing XPath queries against the document, e.g.:
string xml="Your xml string here" ;
XmlDocument doc = new XmlDocument();
doc.LoadXml(xml);
path = "/doc/element1[#id='key1']/element2[. = 'value2']";
Assert.IsTrue(doc.SelectSingleNode(path) != null);
This lets you test not only whether or not your document is semantically valid, but whether or not the method producing it is populating it with the values that you expect.

Fluent Assertions is an excellent library for expressing test assertions in a fluent, easy to read style. It works with all the major Unit Testing frameworks.
It also has some useful XML functionality (all taken from the examples here), for example:
xElementA.Should().Be(xElementB);
xDocument.Should().HaveRoot("configuration");
xDocument.Should().HaveElement("settings");
xElement.Should().HaveAttribute("age", "36");
xElement.Should().HaveElement("address");
xAttribute.Should().HaveValue("Amsterdam");
Note that this works with LINQ-To-XML rather than the XmlDocument object specified in the original question but personally these days I find I'm using LINQ-To-XML as a first choice.
It is also quite easily extensible, should you want to add further XML assertions to fit your needs.

Another possibility might be to use XmlReader and check for an error count > 0. Something like this:
void CheckXml()
{
string _xmlFile = "this.xml";
string _xsdFile = "schema.xsd";
StringCollection _xmlErrors = new StringCollection();
XmlReader reader = null;
XmlReaderSettings settings = new XmlReaderSettings();
settings.ValidationEventHandler += new ValidationEventHandler(this.ValidationEventHandler);
settings.ValidationType = ValidationType.Schema;
settings.IgnoreComments = chkIgnoreComments.Checked;
settings.IgnoreProcessingInstructions = chkIgnoreProcessingInstructions.Checked;
settings.IgnoreWhitespace = chkIgnoreWhiteSpace.Checked;
settings.Schemas.Add(null, XmlReader.Create(_xsdFile));
reader = XmlReader.Create(_xmlFile, settings);
while (reader.Read())
{
}
reader.Close();
Assert.AreEqual(_xmlErrors.Count,0);
}
void ValidationEventHandler(object sender, ValidationEventArgs args)
{
_xmlErrors.Add("<" + args.Severity + "> " + args.Message);
}

Validate against XML schema or DTD, also check key that nodes have the values you expect.

If you have a standard format that you expect the output to be, why not create an XML schema or DTD and validate against that. This won't depend on the data, so will be flexible. Also defining how the XML can be formed can be helpful when designing you system.

This blog post by marianor gives a lightweight way to compare XElement structures, so I'm going to try that before tackling XMLUnit.
The first thing to do is normalize the two XMLs...using Linq... After both elements were normalized, simply you can compare both strings.
The XML is normalized by sorting the element and attribute names.

Validate it against an XSD schema using XmlSchema class. Its found under System.XML i think.
Another option would be to write a serialization class (XMLSerializer) to deserialize your XML into an object. The gain will be that it will implicitly validate your structure and after that the values can be easily accessed for testing using the resulting object.

Another reason to use a Schema to validate against is that while XML nodes are explicitly ordered, XML attributes are not.
So your string comparison of:
Assert.AreEqual(myDoc.OuterXML(),"big string of XML")
would fail if the attributes are in a different order, as could easily happen if one bit of XML was manually created and the other programatically.

Verify the resulting document is well formed
Verify the resulting document is valid
Verify the resulting document is correct.
Presumably, you are crafting an XML document out of useful data, so you will want to ensure that you have the right coverage of inputs for your tests. The most common problems I see are
Incorrectly escaped elements
Incorrectly escaped attributes
Incorrectly escaped element names
Incorrectly escaped attribute names
So if you haven't already done so, you would need to review the XML spec to see what's allowed in each place.
How much "checking" should happen in each test isn't immediately clear. It will depend a lot on what a unit is in your problem space, I suppose. It seems reasonable that each unit test is checking that one piece of data is correctly expressed in the XML. In this case, I'm in agreement with Robert that a simple check that you find the right data at a single XPath location is best.
For larger automated tests, where you want to check the entire document, what I've found to be effective is to have an Expected results which is also a document, and walk through it node by node, using XPath expressions to find the corresponding node in the actual document, and then applying the correct comparison of the data encoded in the two nodes.
With this approach, you'll normally want to catch all failures at once, rather than aborting on first failure, so you may need to be tricksy about how you track where mismatches occurred.
With a bit more work, you can recognize certain element types as being excused from a test (like a time stamp), or to validate that they are pointers to equivalent nodes, or... whatever sort of custom verification you want.

I plan on using this new Approval Testing library to help with XML testing.
It looks to be perfect for the job, but read it first yourself as I don't have experience using it.

why not assume that some commercial xml parser is correct and validate your xml code against it? something like.
Assert.IsTrue(myDoc.Xml.ParseOK)
other than that and if you want to be thorough I'd say you would have to build a parser yourself and validate each rule the xml specification requires.

You can use a DTD to check for the validity of the generated xml.
To test for the correct content I would go for XMLUnit.
Asserting xml using XMLUnit:
XMLUnit.setIgnoreWhitespace(true);
XMLUnit.setIgnoreDiffBetweenTextAndCDATA(true);
Diff diff = new Diff(expectedDocument, obtainedDocument);
XMLAssert.assertXMLIdentical("xml invalid", diff, true);
One thing you might come across is the fact that the generated xml might contain changing identifiers (id/uid attributes or alike). This can be solved by using a DifferenceListener when asserting the generated xml.
Example implementation of such DifferenceListener:
public class IgnoreVariableAttributesDifferenceListener implements DifferenceListener {
private final List<String> IGNORE_ATTRS;
private final boolean ignoreAttributeOrder;
public IgnoreVariableAttributesDifferenceListener(List<String> attributesToIgnore, boolean ignoreAttributeOrder) {
this.IGNORE_ATTRS = attributesToIgnore;
this.ignoreAttributeOrder = ignoreAttributeOrder;
}
#Override
public int differenceFound(Difference difference) {
// for attribute value differences, check for ignored attributes
if (difference.getId() == DifferenceConstants.ATTR_VALUE_ID) {
if (IGNORE_ATTRS.contains(difference.getControlNodeDetail().getNode().getNodeName())) {
return RETURN_IGNORE_DIFFERENCE_NODES_IDENTICAL;
}
}
// attribute order mismatch (optionally ignored)
else if (difference.getId() == DifferenceConstants.ATTR_SEQUENCE_ID && ignoreAttributeOrder) {
return RETURN_IGNORE_DIFFERENCE_NODES_IDENTICAL;
}
// attribute missing / not expected
else if (difference.getId() == DifferenceConstants.ATTR_NAME_NOT_FOUND_ID) {
if (IGNORE_ATTRS.contains(difference.getTestNodeDetail().getValue())) {
return RETURN_IGNORE_DIFFERENCE_NODES_IDENTICAL;
}
}
return RETURN_ACCEPT_DIFFERENCE;
}
#Override
public void skippedComparison(Node control, Node test) {
// nothing to do
}
}
using DifferenceListener:
XMLUnit.setIgnoreWhitespace(true);
XMLUnit.setIgnoreDiffBetweenTextAndCDATA(true);
Diff diff = new Diff(expectedDocument, obtainedDocument);
diff.overrideDifferenceListener(new IgnoreVariableAttributesDifferenceListener(Arrays.asList("id", "uid"), true));
XMLAssert.assertXMLIdentical("xml invalid", diff, true);

Related

Parse XML Webservice response to appropriate type c# [duplicate]

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Closed 4 years ago.
This question's answers are a community effort. Edit existing answers to improve this post. It is not currently accepting new answers or interactions.
Is there a simple method of parsing XML files in C#? If so, what?
It's very simple. I know these are standard methods, but you can create your own library to deal with that much better.
Here are some examples:
XmlDocument xmlDoc= new XmlDocument(); // Create an XML document object
xmlDoc.Load("yourXMLFile.xml"); // Load the XML document from the specified file
// Get elements
XmlNodeList girlAddress = xmlDoc.GetElementsByTagName("gAddress");
XmlNodeList girlAge = xmlDoc.GetElementsByTagName("gAge");
XmlNodeList girlCellPhoneNumber = xmlDoc.GetElementsByTagName("gPhone");
// Display the results
Console.WriteLine("Address: " + girlAddress[0].InnerText);
Console.WriteLine("Age: " + girlAge[0].InnerText);
Console.WriteLine("Phone Number: " + girlCellPhoneNumber[0].InnerText);
Also, there are some other methods to work with. For example, here. And I think there is no one best method to do this; you always need to choose it by yourself, what is most suitable for you.
I'd use LINQ to XML if you're in .NET 3.5 or higher.
Use a good XSD Schema to create a set of classes with xsd.exe and use an XmlSerializer to create a object tree out of your XML and vice versa. If you have few restrictions on your model, you could even try to create a direct mapping between you model classes and the XML with the Xml*Attributes.
There is an introductory article about XML Serialisation on MSDN.
Performance tip: Constructing an XmlSerializer is expensive. Keep a reference to your XmlSerializer instance if you intend to parse/write multiple XML files.
If you're processing a large amount of data (many megabytes) then you want to be using XmlReader to stream parse the XML.
Anything else (XPathNavigator, XElement, XmlDocument and even XmlSerializer if you keep the full generated object graph) will result in high memory usage and also a very slow load time.
Of course, if you need all the data in memory anyway, then you may not have much choice.
Use XmlTextReader, XmlReader, XmlNodeReader and the System.Xml.XPath namespace. And (XPathNavigator, XPathDocument, XPathExpression, XPathnodeIterator).
Usually XPath makes reading XML easier, which is what you might be looking for.
I have just recently been required to work on an application which involved the parsing of an XML document and I agree with Jon Galloway that the LINQ to XML based approach is, in my opinion, the best. I did however have to dig a little to find usable examples, so without further ado, here are a few!
Any comments welcome as this code works but may not be perfect and I would like to learn more about parsing XML for this project!
public void ParseXML(string filePath)
{
// create document instance using XML file path
XDocument doc = XDocument.Load(filePath);
// get the namespace to that within of the XML (xmlns="...")
XElement root = doc.Root;
XNamespace ns = root.GetDefaultNamespace();
// obtain a list of elements with specific tag
IEnumerable<XElement> elements = from c in doc.Descendants(ns + "exampleTagName") select c;
// obtain a single element with specific tag (first instance), useful if only expecting one instance of the tag in the target doc
XElement element = (from c in doc.Descendants(ns + "exampleTagName" select c).First();
// obtain an element from within an element, same as from doc
XElement embeddedElement = (from c in element.Descendants(ns + "exampleEmbeddedTagName" select c).First();
// obtain an attribute from an element
XAttribute attribute = element.Attribute("exampleAttributeName");
}
With these functions I was able to parse any element and any attribute from an XML file no problem at all!
In Addition you can use XPath selector in the following way (easy way to select specific nodes):
XmlDocument doc = new XmlDocument();
doc.Load("test.xml");
var found = doc.DocumentElement.SelectNodes("//book[#title='Barry Poter']"); // select all Book elements in whole dom, with attribute title with value 'Barry Poter'
// Retrieve your data here or change XML here:
foreach (XmlNode book in nodeList)
{
book.InnerText="The story began as it was...";
}
Console.WriteLine("Display XML:");
doc.Save(Console.Out);
the documentation
If you're using .NET 2.0, try XmlReader and its subclasses XmlTextReader, and XmlValidatingReader. They provide a fast, lightweight (memory usage, etc.), forward-only way to parse an XML file.
If you need XPath capabilities, try the XPathNavigator. If you need the entire document in memory try XmlDocument.
I'm not sure whether "best practice for parsing XML" exists. There are numerous technologies suited for different situations. Which way to use depends on the concrete scenario.
You can go with LINQ to XML, XmlReader, XPathNavigator or even regular expressions. If you elaborate your needs, I can try to give some suggestions.
You can parse the XML using this library System.Xml.Linq. Below is the sample code I used to parse a XML file
public CatSubCatList GenerateCategoryListFromProductFeedXML()
{
string path = System.Web.HttpContext.Current.Server.MapPath(_xmlFilePath);
XDocument xDoc = XDocument.Load(path);
XElement xElement = XElement.Parse(xDoc.ToString());
List<Category> lstCategory = xElement.Elements("Product").Select(d => new Category
{
Code = Convert.ToString(d.Element("CategoryCode").Value),
CategoryPath = d.Element("CategoryPath").Value,
Name = GetCateOrSubCategory(d.Element("CategoryPath").Value, 0), // Category
SubCategoryName = GetCateOrSubCategory(d.Element("CategoryPath").Value, 1) // Sub Category
}).GroupBy(x => new { x.Code, x.SubCategoryName }).Select(x => x.First()).ToList();
CatSubCatList catSubCatList = GetFinalCategoryListFromXML(lstCategory);
return catSubCatList;
}
You can use ExtendedXmlSerializer to serialize and deserialize.
Instalation
You can install ExtendedXmlSerializer from nuget or run the following command:
Install-Package ExtendedXmlSerializer
Serialization:
ExtendedXmlSerializer serializer = new ExtendedXmlSerializer();
var obj = new Message();
var xml = serializer.Serialize(obj);
Deserialization
var obj2 = serializer.Deserialize<Message>(xml);
Standard XML Serializer in .NET is very limited.
Does not support serialization of class with circular reference or class with interface property,
Does not support Dictionaries,
There is no mechanism for reading the old version of XML,
If you want create custom serializer, your class must inherit from IXmlSerializable. This means that your class will not be a POCO class,
Does not support IoC.
ExtendedXmlSerializer can do this and much more.
ExtendedXmlSerializer support .NET 4.5 or higher and .NET Core. You can integrate it with WebApi and AspCore.
You can use XmlDocument and for manipulating or retrieve data from attributes you can Linq to XML classes.

XML namespaces and XPath

I have an application that has to load XML document and output nodes depending on XPath.
Suppose I start with a document like this:
<aaa>
...[many nodes here]...
<bbb>text</bbb>
...[many nodes here]...
<bbb>text</bbb>
...[many nodes here]...
</aaa>
With XPath //bbb
So far everything is nice.
And selection doc.SelectNodes("//bbb"); returns the list of required nodes.
Then someone uploads a document with one node like <myfancynamespace:foo/> and extra namespace in the root tag, and everything breaks.
Why? //bbb does not give a damn about myfancynamespace, theoretically it should even be good with //myfancynamespace:foo, as there is no ambiguity, but the expression returns 0 results and that's it.
Is there a workaround for this behavior?
I do have a namespace manager for the document, and I am passing it to the Xpath query. But the namespaces and the prefixes are unknown to me, so I can't add them before the query.
Do I have to pre-parse the document to fill the namespace manager before I do any selections? Why on earth such behavior, it just doesn't make sense.
EDIT:
I'm using:
XmlDocument and XmlNamespaceManager
EDIT2:
XmlDocument doc = new XmlDocument();
doc.XmlResolver = null;
XmlNamespaceManager nsmgr = new XmlNamespaceManager(doc.NameTable);
//I wish I could:
//nsmgr.AddNamespace("magic", "http://magicnamespaceuri/
//...
doc.LoadXML(usersuppliedxml);
XmlNodeList nodes = doc.SelectNodes(usersuppliedxpath, nsmgr);//usersuppliedxpath -> "//bbb"
//nodes.Count should be > 0, but with namespaced document they are 0
EDIT3:
Found an article which describes the actual scenario of the issue with one workaround, but not very pretty workaround: http://codeclimber.net.nz/archive/2008/01/09/How-to-query-a-XPath-doc-that-has-a-default.aspx
Almost seems that stripping the xmlns is the way to go...
You're missing the whole point of XML namespaces.
But if you really need to perform XPath on documents that will use an unknown namespace, and you really don't care about it, you will need to strip it out and reload the document. XPath will not work in a namespace-agnostic way, unless you want to use the local-name() function at every point in your selectors.
private XmlDocument StripNamespace(XmlDocument doc)
{
if (doc.DocumentElement.NamespaceURI.Length > 0)
{
doc.DocumentElement.SetAttribute("xmlns", "");
// must serialize and reload for this to take effect
XmlDocument newDoc = new XmlDocument();
newDoc.LoadXml(doc.OuterXml);
return newDoc;
}
else
{
return doc;
}
}
<myfancynamespace:foo/> is not necessarily the same as <foo/>.
Namespaces do matter. But I can understand your frustration as they usually tend to breaks codes as various implementation (C#, Java, ...) tend to output it differently.
I suggest you change your XPath to allow for accepting all namespaces. For example instead of
//bbb
Define it as
//*[local-name()='bbb']
That should take care of it.
You should describe a bit more detailed what you want to do. The way you ask your question it make no sense at all. The namespace is just a part of the name. Nothing more, nothing less. So your question is the same as asking for an XPath query to get all tags ending with "x". That's not the idea behind XML, but if you have strange reasons to do so: Feel free to iterate over all nodes and implement it yourself. The same applies to functionality you are requesting.
You could use the LINQ XML classes like XDocument. They greatly simplify working with namespaces.

How to iterate over xml using linq2xml or Xquery

I have an incoming file with data as
<root><![CDATA[<defs><elements>
<element><item>aa</item><int>1</int></element>
<element><item>bb</item><int>2</int></element>
<element><item>cc</item><int>3</int></element>
</elements></defs>]]></root>
writing multiple foreach( xElement x in root.Elements ) seems superfluous !
looking for a less verbose method preferably using C#
UPDATE - yes - the input is in a CDATA, rest assured it's not my design and i have ZERO control over it !
Assuming that nasty CDATA section is intentional, and you're only interested in the text content of your leaf elements, you can do something like:
XElement root = XElement.Load(yourFile);
var data = from element in XElement.Parse(root.Value).Descendants("element")
select new {
Item = element.Elements("item").First().Value,
Value = element.Elements("int").First().Value
};
That said, if the code that generates your input file is under your control, consider getting rid of the CDATA section. Storing XML within XML that way is not the way to go most of the time, as it defeats the purpose of the markup language (and requires multiple parser passes, as shown above).

How do I work with an XML tag within a string?

I'm working in Microsoft Visual C# 2008 Express.
Let's say I have a string and the contents of the string is: "This is my <myTag myTagAttrib="colorize">awesome</myTag> string."
I'm telling myself that I want to do something to the word "awesome" - possibly call a function that does something called "colorize".
What is the best way in C# to go about detecting that this tag exists and getting that attribute? I've worked a little with XElements and such in C#, but mostly to do with reading in and out XML files.
Thanks!
-Adeena
Another solution:
var myString = "This is my <myTag myTagAttrib='colorize'>awesome</myTag> string.";
try
{
var document = XDocument.Parse("<root>" + myString + "</root>");
var matches = ((System.Collections.IEnumerable)document.XPathEvaluate("myTag|myTag2")).Cast<XElement>();
foreach (var element in matches)
{
switch (element.Name.ToString())
{
case "myTag":
//do something with myTag like lookup attribute values and call other methods
break;
case "myTag2":
//do something else with myTag2
break;
}
}
}
catch (Exception e)
{
//string was not not well formed xml
}
I also took into account your comment to Dabblernl where you want parse multiple attributes on multiple elements.
You can extract the XML with a regular expression, load the extracted xml string in a XElement and go from there:
string text=#"This is my<myTag myTagAttrib='colorize'>awesome</myTag> text.";
Match match=Regex.Match(text,#"(<MyTag.*</MyTag>)");
string xml=match.Captures[0].Value;
XElement element=XElement.Parse(xml);
XAttribute attribute=element.Attribute("myTagAttrib");
if(attribute.Value=="colorize") DoSomethingWith(element.Value);// Value=awesome
This code will throw an exception if no MyTag element was found, but that can be remedied by inserting a line of:
if(match.Captures.Count!=0)
{...}
It gets even more interesting if the string could hold more than just the MyTag Tag...
I'm a little confused about your example, because you switch between the string (text content), tags, and attributes. But I think what you want is XPath.
So if your XML stream looks like this:
<adeena/><parent><child x="this is my awesome string">This is another awesome string<child/><adeena/>
You'd use an XPath expression that looks like this to find the attribute:
//child/#x
and one like this to find the text value under the child tag:
//child
I'm a Java developer, so I don't know what XML libraries you'd use to do this. But you'll need a DOM parser to create a W3C Document class instance for you by reading in the XML file and then using XPath to pluck out the values.
There's a good XPath tutorial from the W3C schools if you need it.
UPDATE:
If you're saying that you already have an XML stream as String, then the answer is to not read it from a file but from the String itself. Java has abstractions called InputStream and Reader that handle streams of bytes and chars, respectively. The source can be a file, a string, etc. Check your C# DOM API to see if it has something similar. You'll pass the string to a parser that will give back a DOM object that you can manipulate.
Since the input is not well-formed XML you won't be able to parse it with any of the built in XML libraries. You'd need a regular expression to extract the well-formed piece. You could probably use one of the more forgiving HTML parsers like HtmlAgilityPack on CodePlex.
This is my solution to match any type of xml using Regex:
C# Better way to detect XML?
The XmlTextReader can parse XML fragments with a special constructor which may help in this situation, but I'm not positive about that.
There's an in-depth article here:
http://geekswithblogs.net/kobush/archive/2006/04/20/75717.aspx

How does one parse XML files? [closed]

Closed. This question needs to be more focused. It is not currently accepting answers.
Closed 4 years ago.
This question's answers are a community effort. Edit existing answers to improve this post. It is not currently accepting new answers or interactions.
Is there a simple method of parsing XML files in C#? If so, what?
It's very simple. I know these are standard methods, but you can create your own library to deal with that much better.
Here are some examples:
XmlDocument xmlDoc= new XmlDocument(); // Create an XML document object
xmlDoc.Load("yourXMLFile.xml"); // Load the XML document from the specified file
// Get elements
XmlNodeList girlAddress = xmlDoc.GetElementsByTagName("gAddress");
XmlNodeList girlAge = xmlDoc.GetElementsByTagName("gAge");
XmlNodeList girlCellPhoneNumber = xmlDoc.GetElementsByTagName("gPhone");
// Display the results
Console.WriteLine("Address: " + girlAddress[0].InnerText);
Console.WriteLine("Age: " + girlAge[0].InnerText);
Console.WriteLine("Phone Number: " + girlCellPhoneNumber[0].InnerText);
Also, there are some other methods to work with. For example, here. And I think there is no one best method to do this; you always need to choose it by yourself, what is most suitable for you.
I'd use LINQ to XML if you're in .NET 3.5 or higher.
Use a good XSD Schema to create a set of classes with xsd.exe and use an XmlSerializer to create a object tree out of your XML and vice versa. If you have few restrictions on your model, you could even try to create a direct mapping between you model classes and the XML with the Xml*Attributes.
There is an introductory article about XML Serialisation on MSDN.
Performance tip: Constructing an XmlSerializer is expensive. Keep a reference to your XmlSerializer instance if you intend to parse/write multiple XML files.
If you're processing a large amount of data (many megabytes) then you want to be using XmlReader to stream parse the XML.
Anything else (XPathNavigator, XElement, XmlDocument and even XmlSerializer if you keep the full generated object graph) will result in high memory usage and also a very slow load time.
Of course, if you need all the data in memory anyway, then you may not have much choice.
Use XmlTextReader, XmlReader, XmlNodeReader and the System.Xml.XPath namespace. And (XPathNavigator, XPathDocument, XPathExpression, XPathnodeIterator).
Usually XPath makes reading XML easier, which is what you might be looking for.
I have just recently been required to work on an application which involved the parsing of an XML document and I agree with Jon Galloway that the LINQ to XML based approach is, in my opinion, the best. I did however have to dig a little to find usable examples, so without further ado, here are a few!
Any comments welcome as this code works but may not be perfect and I would like to learn more about parsing XML for this project!
public void ParseXML(string filePath)
{
// create document instance using XML file path
XDocument doc = XDocument.Load(filePath);
// get the namespace to that within of the XML (xmlns="...")
XElement root = doc.Root;
XNamespace ns = root.GetDefaultNamespace();
// obtain a list of elements with specific tag
IEnumerable<XElement> elements = from c in doc.Descendants(ns + "exampleTagName") select c;
// obtain a single element with specific tag (first instance), useful if only expecting one instance of the tag in the target doc
XElement element = (from c in doc.Descendants(ns + "exampleTagName" select c).First();
// obtain an element from within an element, same as from doc
XElement embeddedElement = (from c in element.Descendants(ns + "exampleEmbeddedTagName" select c).First();
// obtain an attribute from an element
XAttribute attribute = element.Attribute("exampleAttributeName");
}
With these functions I was able to parse any element and any attribute from an XML file no problem at all!
In Addition you can use XPath selector in the following way (easy way to select specific nodes):
XmlDocument doc = new XmlDocument();
doc.Load("test.xml");
var found = doc.DocumentElement.SelectNodes("//book[#title='Barry Poter']"); // select all Book elements in whole dom, with attribute title with value 'Barry Poter'
// Retrieve your data here or change XML here:
foreach (XmlNode book in nodeList)
{
book.InnerText="The story began as it was...";
}
Console.WriteLine("Display XML:");
doc.Save(Console.Out);
the documentation
If you're using .NET 2.0, try XmlReader and its subclasses XmlTextReader, and XmlValidatingReader. They provide a fast, lightweight (memory usage, etc.), forward-only way to parse an XML file.
If you need XPath capabilities, try the XPathNavigator. If you need the entire document in memory try XmlDocument.
I'm not sure whether "best practice for parsing XML" exists. There are numerous technologies suited for different situations. Which way to use depends on the concrete scenario.
You can go with LINQ to XML, XmlReader, XPathNavigator or even regular expressions. If you elaborate your needs, I can try to give some suggestions.
You can parse the XML using this library System.Xml.Linq. Below is the sample code I used to parse a XML file
public CatSubCatList GenerateCategoryListFromProductFeedXML()
{
string path = System.Web.HttpContext.Current.Server.MapPath(_xmlFilePath);
XDocument xDoc = XDocument.Load(path);
XElement xElement = XElement.Parse(xDoc.ToString());
List<Category> lstCategory = xElement.Elements("Product").Select(d => new Category
{
Code = Convert.ToString(d.Element("CategoryCode").Value),
CategoryPath = d.Element("CategoryPath").Value,
Name = GetCateOrSubCategory(d.Element("CategoryPath").Value, 0), // Category
SubCategoryName = GetCateOrSubCategory(d.Element("CategoryPath").Value, 1) // Sub Category
}).GroupBy(x => new { x.Code, x.SubCategoryName }).Select(x => x.First()).ToList();
CatSubCatList catSubCatList = GetFinalCategoryListFromXML(lstCategory);
return catSubCatList;
}
You can use ExtendedXmlSerializer to serialize and deserialize.
Instalation
You can install ExtendedXmlSerializer from nuget or run the following command:
Install-Package ExtendedXmlSerializer
Serialization:
ExtendedXmlSerializer serializer = new ExtendedXmlSerializer();
var obj = new Message();
var xml = serializer.Serialize(obj);
Deserialization
var obj2 = serializer.Deserialize<Message>(xml);
Standard XML Serializer in .NET is very limited.
Does not support serialization of class with circular reference or class with interface property,
Does not support Dictionaries,
There is no mechanism for reading the old version of XML,
If you want create custom serializer, your class must inherit from IXmlSerializable. This means that your class will not be a POCO class,
Does not support IoC.
ExtendedXmlSerializer can do this and much more.
ExtendedXmlSerializer support .NET 4.5 or higher and .NET Core. You can integrate it with WebApi and AspCore.
You can use XmlDocument and for manipulating or retrieve data from attributes you can Linq to XML classes.

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