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iterating XmlDocument with xpath

How do we iterate an XmlDocument using an xpath?
I'm attempting to return a list of nodes by xpath:
public static List<string> Filter(string xpath, string input, string ns, string nsUrl)
{
var bytes = Encoding.UTF8.GetBytes(input); //i believe this unescapes the string
var stream = new MemoryStream(bytes);
var doc = new XmlDocument();
XmlNamespaceManager namespaceManager = new XmlNamespaceManager(doc.NameTable);
namespaceManager.AddNamespace(ns, nsUrl);
var links = new List<string>();
var nodes = doc.SelectNodes(xpath, namespaceManager);
using (var reader = new XmlTextReader(stream))
{
reader.Namespaces = false;
doc.Load(reader);
}
foreach (XmlNode node in nodes)
{
if (IsNullOrWhiteSpace(node.InnerText))
{
continue;
}
links.Add(node.InnerText);
}
return links;
}
however, the count is always 0 !
I'm using this xpath. notice how i am using only 1 namespace:
/ns0:Visit/ns0:DocumentInterface/ns0:Documents/ns0:Document/ns0:BinaryData
The header of the file looks like this:
<ns0:Visit xmlns:ns0="http://NameSpace.ExternalSchemas.Patient"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
I'm certain that I am using the right xpath because I tested it against my payload:
I'm calling the function this way:
var links = Filter(xpath, xml, "ns0", "http://NameSpace.ExternalSchemas.Patient");
How do we iterate an XmlDocument using an xpath? Perhaps the XmlDocument should be an XDocument instead?

How to get attribute xml without loop c#

i have xml file like this
> <?xml version='1.0' ?>
<config>
<app>
<app version="1.1.0" />
> </app>
</config>
and i want to read attribute version from node app
without any loop like this
while(reader.read()) or foreach etc.
Thanks

XmlDocument document = new XmlDocument();
document.Load("D:/source.xml");
XmlNode appVersion1 = document.SelectSingleNode("//app[#version]/#version");
XmlNode appVersion2 = document["config"]["app"]["app"].Attributes["version"];
Console.WriteLine("{0}, {1}",
appVersion1.Value,
appVersion2.Value);

You can do it this way.
XmlDocument doc = new XmlDocument();
string str = "<config><app><app version=" + "\"1.1.0\"" + "/></app></config>";
doc.LoadXml(str);
var nodes = doc.GetElementsByTagName("app");
foreach (XmlNode node in nodes)
{
if (node.Attributes["version"] != null)
{
string version = node.Attributes["version"].Value;
}
}
And you need to this for loop cause you got two nodes with same name App.
If you have a single node with name App,
XmlDocument doc = new XmlDocument();
string str = "<config><app version=" + "\"1.1.0\"" + "/></config>";
doc.LoadXml(str);
var node = doc.SelectSingleNode("//app");
if (node.Attributes["version"] != null)
{
string version = node.Attributes["version"].Value;
Console.WriteLine(version);
}

You can use linq to do
string stringXml= "yourXml Here";
XElement xdoc = XElement.Parse(stringXml);
var result= xdoc.Descendants("app").FirstOrDefault(x=> x.Attribute("version") != null).attribute("version").Value;
or:
var result = xdoc.Descendants("app").Where(x => x.Attribute("version") != null)
.Select(x => new { Version = x.Value });

how to get the value from innerXMl correctly

I plan to retrieve each suggestion in array and then stroe it in to the list. I have trouble retrieve the option node data, in this pattern {aeroplane,aeroplanes, aerobian} {i}, Any kind soul can help me out with it.
XmlDocument findStringDoc = new XmlDocument();
findStringDoc.Load (Application.dataPath+ "/" + filename);
XmlNodeList nodeList = findStringDoc.SelectNodes("/results/error");
//XmlNodeList suggestionNodeList = findStringDoc.SelectNodes("/results/error/suggestions/option");
foreach(XmlNode xn in nodeList){
errorString.Add(xn["string"].InnerText);
errorType.Add(xn["type"].InnerText);
//string temp = xn["suggestion"].InnerXml;
////TODO: Retrieve suggestions here!
XmlNodeList suggestionNodeList = findStringDoc.SelectNodes("/suggestions");
foreach(XmlNode yn in suggestionNodeList){
option[suggestionNodeList.Count] = yn["option"].InnerText;
Debug.Log(yn["option"].InnerText);
}
suggestionResult.Add (option);
//Debug.Log(suggestionResult);
//XmlNodeList suggestionNodeList = findStringDoc.SelectNodes("/results/error[string='{0}']/suggestions/option",errorString[i]);
}
<results>
<error>
<string>aeroplan</string>
<description>Spelling</description>
<precontext>a</precontext>
<suggestions>
<option>aeroplane</option>
<option>aeroplanes</option>
<option>aerobian</option>
</suggestions>
<type>spelling</type>
</error>
<error>
<string>i</string>
<description>Make I uppercase</description>
<precontext></precontext>
<suggestions>
<option>I</option>
</suggestions>
<type>grammar</type>
<url>http://service.afterthedeadline.com/info.slp?text=i&tags=PRP&engine=1</url>
</error>
</results>

You can use my code below:
private static void GetSuggestionOption(string filename, string value, string optionSuggest)
{
XDocument xDoc = XDocument.Parse(filename);
var parentNode = xDoc.Descendants().Where(x => x.Value == value).Ancestors().FirstOrDefault();
var childNode = parentNode.Descendants().Where(x => x.Name == optionSuggest);
childNode.ToList().ForEach(x => Console.WriteLine(x.Value));
}
Calling: GetSuggestionOption(fileName, "aeroplan", "option");
Happy Coding!

You can use XmlDocument.SelectNodes() method passing suitable XPath string parameter to select specific element(s) from XmlDocument, for example :
public void GetSuggestionOption(string keyword)
{
XmlDocument doc = new XmlDocument();
doc.Load (Application.dataPath+ "/" + filename);
string xpath = string.Format("//error[string='{0}']/suggestions/option", keyword);
XmlNodeList optionSuggestionList = doc.SelectNodes(xpath);
foreach (XmlNode option in optionSuggestionList)
{
Debug.Log(option.InnerXml);
}
}
You can call the method this way for example : GetSuggestionOption("aeroplan")

How to set attribute to an XML element using linq to xml in C#

i've an xml file like
<Root>
<Steps>
<Step Test="SampleTestOne" Status="Fail" />
<Step Test="SampleTestTwo" Status="Fail" />
</Steps>
</Root>
i need to change or overwrite the attribute value of "Status" in the Step element.
Now i'm using XmlDocument for this
like
XmlDocument XDoc = new XmlDocument();
XDoc.Load(Application.StartupPath + "\\Sample.xml");
XmlNodeList NodeList = XDoc.SelectNodes("//Steps/Step");
foreach (XmlNode Node in NodeList)
{
XmlElement Elem = (XmlElement)Node;
String sTemp = Elem.GetAttribute("Test");
if (sTemp == "SampleTestOne")
Elem.SetAttribute("Status", "Pass");
}
I need search the element and to update the status
is there any way to do this using XDocumentin c#
Thanks in advance

string filename = #"C:\Temp\demo.xml";
XDocument document = XDocument.Load(filename);
var stepOnes = document.Descendants("Step").Where(e => e.Attribute("Test").Value == "SampleTestOne");
foreach (XElement element in stepOnes)
{
if (element.Attribute("Status") != null)
element.Attribute("Status").Value = "Pass";
else
element.Add(new XAttribute("Status", "Pass"));
}
document.Save(filename);

You can use this code:
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(xmlFile);
XmlNode node = xmlDoc.SelectSingleNode("Root/Steps/Step");
node.Attributes["Status"].Value = "True";
xmlDoc.Save(xmlFile);

Enumerating Linq.Xelement

How to adjust this code to work when RESPONSE is no more string but Linq.Xelement?
String response = "anyxml data";
XmlDocument xmlDocument = LoadXMLDocument(response);
XmlNodeList nodeList = xmlDocument.GetElementsByTagName("fql_query_response");
if (nodeList != null && nodeList.Count > 0)
{
if (nodeList[0].HasChildNodes)
{
XmlNodeList results = xmlDocument.GetElementsByTagName("event_member");
Dictionary<string, EventUser> eventUserDict = new Dictionary<string, EventUser>();
foreach (XmlNode node in results)
{
myuids.Add(Int64.Parse(node.FirstChild.InnerText));
}
}

Do you mean you want to create an XmlDocument from an XElement?
The simplest way to do that may well be this:
XmlDocument doc = new XmlDocument();
using (XmlReader reader = element.CreateReader())
{
doc.Load(reader);
}
However, I have to say the code would probably be simpler if you just converted it all to LINQ to XML, which is generally a nicer API to start with. Is there any reason why you want to stay with XmlDocument?

You can use XElement.ToString() to create an XML string from the XElement which you can load into your XmlDocument:
XmlDocument xmlDocument = LoadXMLDocument(yourXElement.ToString());