Parse XML in C#

Question

Hello I want to know how can I parse this simple XML file content in C#. I can have multiple "in" elements, and from those I want to use date, min, max and state child values.

<out>
<in>
<id>16769</id>
<date>29-10-2010</date>
<now>12</now>
<min>12</min>
<max>23</max>
<state>2</state>
<description>enter text</description>
</in>

<in>
<id>7655</id>
<date>12-10-2010</date>
<now>1</now>
<min>1</min>
<max>2</max>
<state>0</state>
<description>enter text</description>
</in>
</out>

Answer 1

The System.XML namespace has all sorts of tools for parsing, reading, and writing XML data. By the way, your XML isn't well-formed; you've got two <out> elements, but only one </out> element.

Answer 2

You need System.XML, starting with XmlDocument.Load(filename).

Once you have the XmlDocument loaded, you can drill down into it as needed using the built-in .Net XML object model, starting from XmlDocument level. You can walk the tree recursively in a pretty intuitive way, capturing what you want from each XmlNode as you go.

Alternatively (and preferably) you can quickly locate all XmlNodes in your XmlDocument that match certain conditions using XPath - examples here. An example of usage in C# is XmlNode.SelectNodes.

using System;
using System.IO;
using System.Xml;

public class Sample {

  public static void Main() {

    XmlDocument doc = new XmlDocument();
    doc.Load("booksort.xml");

    XmlNodeList nodeList;
    XmlNode root = doc.DocumentElement;

    nodeList=root.SelectNodes("descendant::book[author/last-name='Austen']");

    //Change the price on the books.
    foreach (XmlNode book in nodeList)
    {
      book.LastChild.InnerText="15.95";
    }

    Console.WriteLine("Display the modified XML document....");
    doc.Save(Console.Out);

  }
}

Answer 3

Examples can be found here http://www.c-sharpcorner.com/uploadfile/mahesh/readwritexmltutmellli2111282005041517am/readwritexmltutmellli21.aspx

Answer 4

Linq to xml is also helpful for parsing xml -

http://msdn.microsoft.com/en-us/library/bb387098.aspx

Also - http://msdn.microsoft.com/library/bb308960.aspx

Answer 5

This might be beyond what you want to do, but worth mentioning...

I hate parsing XML. Seriously, I almost refuse to do it, especially since .NET can do it for me. What I would do is create an "In" object that has the properties above. You probably have one already, or it would take 60 seconds to create. You'll also need a List of In objects called "Out".

Then just deserialze the XML into the objects. This takes just a few lines of code. Here is an example. BTW, this makes changing and re-saving the data just as easy.

How to serialize/deserialize