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

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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.

Copy or clone a specific Element from XML to the same XML

i want to copy or clone a specific node or Element from XML. I tried many codes, but no one worked. I am program with C#.
Here is my XML, I hope my problem is clear!
This is my XML before
I want this XML
I can´t do this manually, because I need more than 30 Tools more.

it really depends on what you are using to parse the xml.
I will give you info for the two most used classes for parsing an xml in .NET.
XmlDocument: then you can use .CloneNode
XDocument: then you can do something like this:
XElement toCopy = ...;
XElement copy = XElement.Parse(toCopy.ToString());
If you are not familiar with xml processing in .NET, there is enough information in msdn for XDocument and XmlDocument.

C#: Line information when parsing XML with XmlDocument

What are my options for parsing an XML file with XmlDocument and still retain line information for error messages later on? (as an aside, is it possible to do the same thing with XML Deserialisation?)
Options seem to include:
Extending the DOM and using IXmlLineInfo
Using XPathDocument

The only other option I know of is XDocument.Load(), whose overloads accept LoadOptions.SetLineInfo. This would be consumed in much the same way as an XmlDocument.
Example

(Expanding answer from #Andy's comment)
There is no built in way to do this using XmlDocument (if you are using XDocument, you can use the XDocument.Load() overload which accepts LoadOptions.SetLineInfo - see this question).
While there's no built-in way, you can use the PositionXmlDocument wrapper class from here (from the SharpDevelop project):
https://github.com/icsharpcode/WpfDesigner/blob/5a994b0ff55b9e8f5c41c4573a4e970406ed2fcd/WpfDesign.XamlDom/Project/PositionXmlDocument.cs
In order to use it, you will need to use the Load overload that accepts an XmlReader (the other Load overloads will go to the regular XmlDocument class, which will not give you line number information). If you are currently using the XmlDocument.Load overload that accepts a filename, you will need to change your code as follows:
using (var reader = new XmlTextReader(filename))
{
var doc = new PositionXmlDocument();
doc.Load(reader);
}
Now, you should be able to cast any XmlNode from this document to a PositionXmlElement to retrieve line number and column:
var node = doc.ChildNodes[1];
var elem = (PositionXmlElement) node;
Console.WriteLine("Line: {0}, Position: {1}", elem.LineNumber, elem.LinePosition);

XDocument or XmlDocument

I am now learning XmlDocument but I've just ran into XDocument and when I try to search the difference or benefits of them I can't find something useful, could you please tell me why you would use one over another ?

If you're using .NET version 3.0 or lower, you have to use XmlDocument aka the classic DOM API. Likewise you'll find there are some other APIs which will expect this.
If you get the choice, however, I would thoroughly recommend using XDocument aka LINQ to XML. It's much simpler to create documents and process them. For example, it's the difference between:
XmlDocument doc = new XmlDocument();
XmlElement root = doc.CreateElement("root");
root.SetAttribute("name", "value");
XmlElement child = doc.CreateElement("child");
child.InnerText = "text node";
root.AppendChild(child);
doc.AppendChild(root);
and
XDocument doc = new XDocument(
new XElement("root",
new XAttribute("name", "value"),
new XElement("child", "text node")));
Namespaces are pretty easy to work with in LINQ to XML, unlike any other XML API I've ever seen:
XNamespace ns = "http://somewhere.com";
XElement element = new XElement(ns + "elementName");
// etc
LINQ to XML also works really well with LINQ - its construction model allows you to build elements with sequences of sub-elements really easily:
// Customers is a List<Customer>
XElement customersElement = new XElement("customers",
customers.Select(c => new XElement("customer",
new XAttribute("name", c.Name),
new XAttribute("lastSeen", c.LastOrder)
new XElement("address",
new XAttribute("town", c.Town),
new XAttribute("firstline", c.Address1),
// etc
));
It's all a lot more declarative, which fits in with the general LINQ style.
Now as Brannon mentioned, these are in-memory APIs rather than streaming ones (although XStreamingElement supports lazy output). XmlReader and XmlWriter are the normal ways of streaming XML in .NET, but you can mix all the APIs to some extent. For example, you can stream a large document but use LINQ to XML by positioning an XmlReader at the start of an element, reading an XElement from it and processing it, then moving on to the next element etc. There are various blog posts about this technique, here's one I found with a quick search.

I am surprised none of the answers so far mentions the fact that XmlDocument provides no line information, while XDocument does (through the IXmlLineInfo interface).
This can be a critical feature in some cases (for example if you want to report errors in an XML, or keep track of where elements are defined in general) and you better be aware of this before you happily start to implement using XmlDocument, to later discover you have to change it all.

XmlDocument is great for developers who are familiar with the XML DOM object model. It's been around for a while, and more or less corresponds to a W3C standard. It supports manual navigation as well as XPath node selection.
XDocument powers the LINQ to XML feature in .NET 3.5. It makes heavy use of IEnumerable<> and can be easier to work with in straight C#.
Both document models require you to load the entire document into memory (unlike XmlReader for example).

As mentioned elsewhere, undoubtedly, Linq to Xml makes creation and alteration of xml documents a breeze in comparison to XmlDocument, and the XNamespace ns + "elementName" syntax makes for pleasurable reading when dealing with namespaces.
One thing worth mentioning for xsl and xpath die hards to note is that it IS possible to still execute arbitrary xpath 1.0 expressions on Linq 2 Xml XNodes by including:
using System.Xml.XPath;
and then we can navigate and project data using xpath via these extension methods:
XPathSelectElement - Single Element
XPathSelectElements - Node Set
XPathEvaluate - Scalars and others
For instance, given the Xml document:
<xml>
<foo>
<baz id="1">10</baz>
<bar id="2" special="1">baa baa</bar>
<baz id="3">20</baz>
<bar id="4" />
<bar id="5" />
</foo>
<foo id="123">Text 1<moo />Text 2
</foo>
</xml>
We can evaluate:
var node = xele.XPathSelectElement("/xml/foo[#id='123']");
var nodes = xele.XPathSelectElements(
"//moo/ancestor::xml/descendant::baz[#id='1']/following-sibling::bar[not(#special='1')]");
var sum = xele.XPathEvaluate("sum(//foo[not(moo)]/baz)");

XDocument is from the LINQ to XML API, and XmlDocument is the standard DOM-style API for XML. If you know DOM well, and don't want to learn LINQ to XML, go with XmlDocument. If you're new to both, check out this page that compares the two, and pick which one you like the looks of better.
I've just started using LINQ to XML, and I love the way you create an XML document using functional construction. It's really nice. DOM is clunky in comparison.

Also, note that XDocument is supported in Xbox 360 and Windows Phone OS 7.0.
If you target them, develop for XDocument or migrate from XmlDocument.

I believe that XDocument makes a lot more object creation calls. I suspect that for when you're handling a lot of XML documents, XMLDocument will be faster.
One place this happens is in managing scan data. Many scan tools output their data in XML (for obvious reasons). If you have to process a lot of these scan files, I think you'll have better performance with XMLDocument.

C#, XML Query Question

I have tons of XML files all containing a the same XML Document, but with different values. But the structure is the same for each file.
Inside this file I have a datetime field.
What is the best, most efficient way to query these XML files? So I can retrieve for example... All files where the datetime field = today's date?
I'm using C# and .net v2. Should I be using XML objects to achieve this or text in file search routines?
Some code examples would be great... or just the general theory, anything would help, thanks...

This depends on the size of those files, and how complex the data actually is. As far as I understand the question, for this kind of XML data, using an XPath query and going through all the files might be the best approach, possibly caching the files in order to lessen the parsing overhead.
Have a look at:
XPathDocument, XmlDocument classes and XPath queries
http://support.microsoft.com/kb/317069
Something like this should do (not tested though):
XmlNamespaceManager nsmgr = new XmlNamespaceManager(new NameTable());
// if required, add your namespace prefixes here to nsmgr
XPathExpression expression = XPathExpression.Compile("//element[#date='20090101']", nsmgr); // your query as XPath
foreach (string fileName in Directory.GetFiles("PathToXmlFiles", "*.xml")) {
XPathDocument doc;
using (XmlTextReader reader = new XmlTextReader(fileName, nsmgr.NameTable)) {
doc = new XPathDocument(reader);
}
if (doc.CreateNavigator().SelectSingleNode(expression) != null) {
// matching document found
}
}
Note: while you can also load a XPathDocument directly from a URI/path, using the reader makes sure that the same nametable is being used as the one used to compile the XPath query. If a different nametable was being used, you'd not get results from the query.

You might look into running XSL queries. See also XSLT Tutorial, XML transformation using Xslt in C#, How to query XML with an XPath expression by using Visual C#.
This question also relates to another on Stack Overflow: Parse multiple XML files with ASP.NET (C#) and return those with particular element. The accepted answer there, though, suggests using Linq.

If it is at all possible to move to C# 3.0 / .NET 3.5, LINQ-to-XML would be by far the easiest option.
With .NET 2.0, you're stuck with either XML objects or XSL.