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Get xml node using c#

I have a request that returns a large xml file. I have the file in a XmlDocument type in my application. From that Doc how can I read an element like this:
<gphoto:videostatus>final</gphoto:videostatus>
I would like to pull that value final from that element. Also If i have multiple elements as well, can I pull that into a list? thanks for any advice.

If you already have an XmlDocument then you can use the function GetElementsByTagName() to create an XmlNodeList that can be accessed similar to an array.
http://msdn.microsoft.com/en-us/library/dc0c9ekk.aspx
//Create the XmlDocument.
XmlDocument doc = new XmlDocument();
doc.Load("books.xml");
//Display all the book titles.
XmlNodeList elemList = doc.GetElementsByTagName("title");
for (int i=0; i < elemList.Count; i++)
{
Console.WriteLine(elemList[i].InnerXml);
}

You can select nodes using XPath and SelectSingleNode SelectNodes. Look at http://www.codeproject.com/Articles/9494/Manipulate-XML-data-with-XPath-and-XmlDocument-C for examples. Then you can use for example InnerText to get final. Maybe you need to work with namespaces (gphoto). The //videostatus would select all videostatus elements

You can try using LINQ
XNamespace ns = XNamespace.Get(""); //use the xmnls namespace here
XElement element = XElement.Load(""); // xml file path
var result = element.Descendants(ns + "videostatus")
.Select(o =>o.Value).ToList();
foreach(var values in value)
{
}
Thanks
Deepu

How to replace all "values" in an XML document with "0.0" using C# (preferably LINQ)?

This is not a homework; I need this for my unit tests.
Sample input: <rows><row><a>1234</a><b>Hello</b>...</row><row>...</rows>.
Sample output: <rows><row><a>0.0</a><b>0.0</b>...</row><row>...</rows>.
You may assume that the document starts with <rows> and that parent node has children named <row>. You do not know the name of nodes a, b, etc.
For extra credit: how to make this work with an arbitrary well-formed, "free-form" XML?
I have tried this with a regex :) without luck. I could make it "non-greedy on the right", but not on the left. Thanks for your help.
EDIT: Here is what I tried:
private static string ReplaceValuesWithZeroes(string gridXml)
{
Assert.IsTrue(gridXml.StartsWith("<row>"), "Xml representation must start with '<row>'.");
Assert.IsTrue(gridXml.EndsWith("</row>"), "Xml representation must end with '<row>'.");
gridXml = "<deleteme>" + gridXml.Trim() + "</deleteme>"; // Fake parent.
var xmlDoc = XDocument.Parse(gridXml);
var descendants = xmlDoc.Root.Descendants("row");
int rowCount = descendants.Count();
for (int rowNumber = 0; rowNumber < rowCount; rowNumber++)
{
var row = descendants.ElementAt(0);
Assert.AreEqual<string>(row.Value /* Does not work */, String.Empty, "There should be nothing between <row> and </row>!");
Assert.AreEqual<string>(row.Name.ToString(), "row");
var rowChildren = row.Descendants();
foreach (var child in rowChildren)
{
child.Value = "0.0"; // Does not work.
}
}
// Not the most efficient but still fast enough.
return xmlDoc.ToString().Replace("<deleteme>", String.Empty).Replace("</deleteme>", String.Empty);
}

XmlDocument doc = new XmlDocument();
doc.LoadXml(xml);
foreach (XmlElement el in doc.SelectNodes("//*[not(*)]"))
el.InnerText = "0.0";
xml = doc.OuterXml;
or to be more selective about non-empty text nodes:
foreach (XmlText el in doc.SelectNodes("//text()[.!='']"))
el.InnerText = "0.0";

XDocument xml = XDocument.Load(myXmlFile);
foreach (var element in xml.Descendants("row").SelectMany(r => r.Elements()))
{
element.Value = "0.0";
}
Note that this general search for "Desscendants('row')" is not very efficient--but it satisfies the 'arbitrary format' requirement.

You should take look at HTML Agility Pack. It allows you to treat html documents as well-formed xml's, therefore you can parse it and change values.

I think you can use Regex.Replace method in C#. I used the below regex to replace all the XML elements values:
[>]+[a-zA-Z0-9]+[<]+
This will basically match text starting with a '>'{some text alphabets or number}'<'.
I was able to use this successfully in Notepad++. You can write a small program as well using this.

How to read XML attributes in C#?

I have several XML files that I wish to read attributes from. My main objective is to apply syntax highlighting to rich text box.
For example in one of my XML docs I have: <Keyword name="using">[..] All the files have the same element: Keyword.
So, how can I get the value for the attribute name and put them in a collection of strings for each XML file.
I am using Visual C# 2008.

The other answers will do the job - but the syntax highlighting thingy and the several xml files you say you have makes me thinks you need something faster, why not use a lean and mean XmlReader?
private string[] getNames(string fileName)
{
XmlReader xmlReader = XmlReader.Create(fileName);
List<string> names = new List<string>();
while (xmlReader.Read())
{
//keep reading until we see your element
if (xmlReader.Name.Equals("Keyword") && (xmlReader.NodeType == XmlNodeType.Element))
{
// get attribute from the Xml element here
string name = xmlReader.GetAttribute("name");
// --> now **add to collection** - or whatever
names.Add(name);
}
}
return names.ToArray();
}
Another good option would be the XPathNavigator class - which is faster than XmlDoc and you can use XPath.
Also I would suggest to go with this approach only IFF after you try with the straightforward options you're not happy with performance.

You could use XPath to get all the elements, then a LINQ query to get the values on all the name atttributes you find:
XDocument doc = yourDocument;
var nodes = from element in doc.XPathSelectElements("//Keyword")
let att = element.Attribute("name")
where att != null
select att.Value;
string[] names = nodes.ToArray();
The //Keyword XPath expression means, "all elements in the document, named "Keyword".
Edit: Just saw that you only want elements named Keyword. Updated the code sample.

Like others, I would suggest using LINQ to XML - but I don't think there's much need to use XPath here. Here's a simple method to return all the keyword names within a file:
static IEnumerable<string> GetKeywordNames(string file)
{
return XDocument.Load(file)
.Descendants("Keyword")
.Attributes("name")
.Select(attr => attr.Value);
}
Nice and declarative :)
Note that if you're going to want to use the result more than once, you should call ToList() or ToArray() on it, otherwise it'll reload the file each time. Of course you could change the method to return List<string> or string[] by -adding the relevant call to the end of the chain of method calls, e.g.
static List<string> GetKeywordNames(string file)
{
return XDocument.Load(file)
.Descendants("Keyword")
.Attributes("name")
.Select(attr => attr.Value)
.ToList();
}
Also note that this just gives you the names - I would have expected you to want the other details of the elements, in which case you'd probably want something slightly different. If it turns out you need more, please let us know.

You could use LINQ to XML.
Example:
var xmlFile = XDocument.Load(someFile);
var query = from item in xmlFile.Descendants("childobject")
where !String.IsNullOrEmpty(item.Attribute("using")
select new
{
AttributeValue = item.Attribute("using").Value
};

You'll likely want to use XPath. //Keyword/#name should get you all of the keyword names.
Here's a good introduction: .Net and XML XPath Queries

**<Countries>
<Country name ="ANDORRA">
<state>Andorra (general)</state>
<state>Andorra</state>
</Country>
<Country name ="United Arab Emirates">
<state>Abu Z¸aby</state>
<state>Umm al Qaywayn</state>
</Country>**
public void datass(string file)
{
string file = HttpContext.Current.Server.MapPath("~/App_Data/CS.xml");
XmlDocument doc = new XmlDocument();
if (System.IO.File.Exists(file))
{
//Load the XML File
doc.Load(file);
}
//Get the root element
XmlElement root = doc.DocumentElement;
XmlNodeList subroot = root.SelectNodes("Country");
for (int i = 0; i < subroot.Count; i++)
{
XmlNode elem = subroot.Item(i);
string attrVal = elem.Attributes["name"].Value;
Response.Write(attrVal);
XmlNodeList sub = elem.SelectNodes("state");
for (int j = 0; j < sub.Count; j++)
{
XmlNode elem1 = sub.Item(j);
Response.Write(elem1.InnerText);
}
}
}

How to Parse XML file in c# (youtube api result)?

I'm trying to parse XML returned from the Youtue API. The APIcalls work correctly and creates an XmlDocument. I can get an XmlNodeList of the "entry" tags, but I'm not sure how to get the elements inside such as the , , etc...
XmlDocument xmlDoc = youtubeService.GetSearchResults(search.Term, "published", 1, 50);
XmlNodeList listNodes = xmlDoc.GetElementsByTagName("entry");
foreach (XmlNode node in listNodes)
{
//not sure how to get elements in here
}
The XML document schema is shown here: http://code.google.com/apis/youtube/2.0/developers_guide_protocol_understanding_video_feeds.html
I know that node.Attributes is the wrong call, but am not sure what the correct one is?
By the way, if there is a better way (faster, less memory) to do this by serializing it or using linq, I'd be happy to use that instead.
Thanks for any help!

Here some examples reading the XmlDocument. I don't know whats fastest or what needs less memory - but i would prefer Linq To Xml because of its clearness.
XmlDocument xmlDoc = youtubeService.GetSearchResults(search.Term, "published", 1, 50);
XmlNodeList listNodes = xmlDoc.GetElementsByTagName("entry");
foreach (XmlNode node in listNodes)
{
// get child nodes
foreach (XmlNode childNode in node.ChildNodes)
{
}
// get specific child nodes
XPathNavigator navigator = node.CreateNavigator();
XPathNodeIterator iterator = navigator.Select(/* xpath selector according to the elements/attributes you need */);
while (iterator.MoveNext())
{
// f.e. iterator.Current.GetAttribute(), iterator.Current.Name and iterator.Current.Value available here
}
}
and the linq to xml one:
XmlDocument xmlDoc = youtubeService.GetSearchResults(search.Term, "published", 1, 50);
XDocument xDoc = XDocument.Parse(xmlDoc.OuterXml);
var entries = from entry in xDoc.Descendants("entry")
select new
{
Id = entry.Element("id").Value,
Categories = entry.Elements("category").Select(c => c.Value)
};
foreach (var entry in entries)
{
// entry.Id and entry.Categories available here
}

I realise this has been answered and LINQ to XML is what I'd go with but another option would be XPathNavigator. Something like
XPathNavigator xmlNav = xmlDoc.CreateNavigator();
XPathNodeIterator xmlitr = xmlNav.Select("/XPath/expression/here")
while (xmlItr.MoveNext()) ...
The code is off the top of my head so it may be wrong and there may be a better way with XPathNavigator but it should give you the general idea

You could use XSD.exe to generate a class based on the schema provided. Once generated, you could then parse the XML response into the strongly typed class.
string xmlResponse = GetMyYouTubeStuff();
MyYouTubeClass response = null;
XmlHelper<MyYouTubeClass> xmlHelper = new XmlHelper<MyYouTubeClass>();
response = xmlHelper.Deserialize(xmlResponse);
And the class for deserializing it...
public class XmlHelper<T>
{
public T Deserialize(string xml)
{
XmlSerializer xs = new XmlSerializer(typeof(T));
Byte[] byteArray = new UTF8Encoding().GetBytes(xml);
MemoryStream memoryStream = new MemoryStream(byteArray);
XmlTextReader xmlTextReader = new XmlTextReader(memoryStream);
T retObj = (T)xs.Deserialize(xmlTextReader);
return retObj;
}
}
There's also another way here.

C# how can I get all elements name from a xml file

I'd like to get all the element name from a xml file, for example the xml file is,
<BookStore>
<BookStoreInfo>
<Address />
<Tel />
<Fax />
<BookStoreInfo>
<Book>
<BookName />
<ISBN />
<PublishDate />
</Book>
<Book>
....
</Book>
</BookStore>
I would like to get the element's name of "BookName". "ISBN" and "PublishDate " and only those names, not include " BookStoreInfo" and its child node's name
I tried several ways, but doesn't work, how can I do it?

Well, with XDocument and LINQ-to-XML:
foreach(var name in doc.Root.DescendantNodes().OfType<XElement>()
.Select(x => x.Name).Distinct())
{
Console.WriteLine(name);
}
There are lots of similar routes, though.

Using XPath
XmlDocument xdoc = new XmlDocument();
xdoc.Load(something);
XmlNodeList list = xdoc.SelectNodes("//BookStore");
gives you a list with all nodes in the document named BookStore

I agree with Adam, the ideal condition is to have a schema that defines the content of xml document. However, sometimes this is not possible. Here is a simple method for iterating all of the nodes of an xml document and using a dictionary to store the unique local names. I like to keep track of the depth of each local name, so I use a list of int to store the depth. Note that the XmlReader is "easy on the memory" since it does not load the entire document as the XmlDocument does. In some instances it makes little difference because the size of the xml data is small. In the following example, an 18.5MB file is read with an XmlReader. Using an XmlDocument to load this data would have been less effecient than using an XmlReader to read and sample its contents.
string documentPath = #"C:\Docs\cim_schema_2.18.1-Final-XMLAll\all_classes.xml";
Dictionary<string, List<int>> nodeTable = new Dictionary<string, List<int>>();
using (XmlReader reader = XmlReader.Create(documentPath))
{
while (!reader.EOF)
{
if (reader.NodeType == XmlNodeType.Element)
{
if (!nodeTable.ContainsKey(reader.LocalName))
{
nodeTable.Add(reader.LocalName, new List<int>(new int[] { reader.Depth }));
}
else if (!nodeTable[reader.LocalName].Contains(reader.Depth))
{
nodeTable[reader.LocalName].Add(reader.Depth);
}
}
reader.Read();
}
}
Console.WriteLine("The node table has {0} items.",nodeTable.Count);
foreach (KeyValuePair<string, List<int>> kv in nodeTable)
{
Console.WriteLine("{0} [{1}]",kv.Key, kv.Value.Count);
for (int i = 0; i < kv.Value.Count; i++)
{
if (i < kv.Value.Count-1)
{
Console.Write("{0}, ", kv.Value[i]);
}
else
{
Console.WriteLine(kv.Value[i]);
}
}
}

The purists way of doing this (and, to be fair, the right way) would be to have a schema contract definition and read it in that way. That being said, you could do something like this...
List<string> nodeNames = new List<string>();
foreach(System.Xml.XmlNode node in doc.SelectNodes("BookStore/Book"))
{
foreach(System.Xml.XmlNode child in node.Children)
{
if(!nodeNames.Contains(child.Name)) nodeNames.Add(child.Name);
}
}
This is, admittedly, a rudimentary method for obtaining the list of distinct node names for the Book node's children, but you didn't specify much else in the way of your environment (if you have 3.5, you could use LINQ to XML to make this a little prettier, for example), but this should get the job done regardless of your environment.

If you're using C# 3.0, you can do the following:
var data = XElement.Load("c:/test.xml"); // change this to reflect location of your xml file
var allElementNames =
(from e in in data.Descendants()
select e.Name).Distinct();

You can try doing it using XPATH.
XmlDocument doc = new XmlDocument();
doc.LoadXml("xml string");
XmlNodeList list = doc.SelectNodes("//BookStore/Book");

If BookStore is ur root element then u can try following code
XmlDocument doc = new XmlDocument();
doc.Load(configPath);
XmlNodeList list = doc.DocumentElement.GetElementsByTagName("Book");
if (list.Count != 0)
{
for (int i = 0; i < list[0].ChildNodes.Count; i++)
{
XmlNode child = list[0].ChildNodes[i];
}
}