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Reading XML file results in index out of range exception

Using C# I have an XML file like
<?xml version="1.0" encoding="utf-8"?>
<root>
<Account>
<name>Jani</name>
</Account>
</root>
and I also have a function to read the name node as:
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load("lib//user.xml");
XmlNode node;
node = xmlDoc.DocumentElement;
string name = node.Attributes[0].Value;
label1.Text = name.ToString();
but I am getting index out of range error as:
Why is this happening?

node = xmlDoc.DocumentElement;
string name = node.Attributes[0].Value;
node is your root node. Which looks like this:
<root>
How many attributes does it have? None, as it turns out. An attribute in XML is one of these bar="baz" things:
<foo bar="baz">
node.Attributes[0] refers to the first attribute. There is no first attribute, there's no second attribute -- you didn't use attributes in this XML at all. Hence, that's out of range. There's no first item in an empty collection.
What you want is an element named name, which is farther down inside your XML tree.
Probably this:
var node = xmlDoc.DocumentElement.SelectSingleNode("/root/Account/name");
And then you'll want to look at node.InnerText to get "Jani" out of it.

You are trying to read node.Attributes[0].Value but there is no attribtues in your sample XML file. Not sure of the exact syntax but it should probably be closer to node.Value

As mentioned by other answers, your current XML does not have attributes.
private void DoIt()
{
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(#"M:\StackOverflowQuestionsAndAnswers\38924171\38924171\data.xml");
XmlNode node;
node = xmlDoc.DocumentElement;
//string name = node.Attributes[0].Value;
string name = node["Account"].InnerText;
}
If your XML did have attributes
<?xml version="1.0" encoding="utf-8"?>
<root>
<Account name="Jani" />
</root>
Then you could do this:
private void DoItAgain()
{
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(#"M:\StackOverflowQuestionsAndAnswers\38924171\38924171\data2.xml");
XmlNode node;
node = xmlDoc.DocumentElement;
string name = node["Account"].Attributes[0].Value;
}

C# how to create a custom xml document

I'm really just trying to create a custom xml document for simple configuration processing.
XmlDocument xDoc = new XmlDocument();
string[] NodeArray = { "Fruits|Fruit", "Vegetables|Veggie"};
foreach (string node in NodeArray)
{
XmlNode xmlNode = xDoc.CreateNode(XmlNodeType.Element,node.Split('|')[0],null);
//xmlNode.Value = node.Split('|')[0];
xmlNode.InnerText = node.Split('|')[1];
xDoc.DocumentElement.AppendChild(xmlNode);
}
What i'm trying to get is this.
<?xml version="1.0" encoding="ISO-8859-1"?>
<Fruits>Fruit</Fruits>
<Vegetables>Veggie</Vegetables>
i get not set to value of an object at xDoc.DocumentElement.AppendChild(xmlNode);

Unfortunately, You can't make that XML structure.
All XML documents must have a single root node. You can't have more.
Try something like this
XmlDocument xDoc = new XmlDocument();
xDoc.AppendChild( xDoc.CreateElement("root"));
string[] NodeArray = { "Fruits|Fruit", "Vegetables|Veggie" };
foreach (string node in NodeArray)
{
XmlNode xmlNode = xDoc.CreateNode(XmlNodeType.Element, node.Split('|')[0], null);
//xmlNode.Value = node.Split('|')[0];
xmlNode.InnerText = node.Split('|')[1];
xDoc.DocumentElement.AppendChild(xmlNode);
}

It is not possible to have that XML structure as XML MUST have a single root element. You may want to try:
<?xml version="1.0" encoding="ISO-8859-1"?>
<items>
<Fruits>Fruit</Fruits>
<Vegetables>Veggie</Vegetables>
</items>

How to get element value using c#

XML file:
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<content>
<FingerPrintUserDetails>
<UserID>e57645</UserID>
<UserName>Jill</UserName>
<FPData>AQAAABQAAAD0AAAAAQASAAEAWgAAAAAA8AAAAHfrWpB6BHZBL10voxpdxu2Km5XVNh*oUNC80Rvpql3RhlqOiBPeet6iRPwb/BdN1fCF4Y/WHbQ40*mqoUKqilgN7bUqNuXP7M299HUWtoAGEO3nDKXXAnHd7dgytZbmHVv*mRBPJDSRw9VY/R1yOIu2cCDlLM*F8Q1lvTfMFDdfwNZynI0e2ZauCF58f0UX56XLFBallaAauxP5mvvhUmcmc6ITg7RhH9wc4181kgPjCuZg38pQepE5U07XIa3hQP8fwxPzdprifXECgB1Z3pTXWQP0q4ZD0Inlbq6Gszo1ucPrhQA0jYQRXtJUVuyBeg</FPData>
<Address>Pune</Address>
<ContactNo>848488484884</ContactNo>
</FingerPrintUserDetails>
<FingerPrintUserDetails>
<UserID>444</UserID>
<UserName>John</UserName>
<FPData>AQAAABQAAADkAAAAAQASAAEAZAAAAAAA4AAAAPLnmQ8FymAAHWYutR5pdtYvfDVmjsqLeli8tOSTFAtw6AkfA0r8XwrMzp9jFZJI7DlBk4G94BMq55gPEG7uBLZUNYrvhv0jDlDFMOjWGJ9RoWekFveTC*oZ7Tq/xmxuvY6FzLHVo*xzdKQI73Y0f9/eeMC0OgqnbQ3I0IP6cTkkKnTUZJOXKr7IFPHkjJAvCDmU7ec4vG50JHdBJIObmbzVcO0huTUQyE7CR1qYkUjmNFKgVKWPLRupEk4l/Ek0BuAba*9JlhBVUHzZuKbDQLc9lTFwevAgDuuAwxfZaLS*</FPData>
<Address>nagpur</Address>
<ContactNo>464645763</ContactNo>
</FingerPrintUserDetails>
<FingerPrintUserDetails>
<UserID>5555</UserID>
<UserName>Jack</UserName>
<FPData>AQAAABQAAAAEAQAAAQASAAEAZAAAAAAA9AAAAPz5mQO3uTeXLfU5Mb74XbCX5rERGZFPQMVG1vPpX87306O5oURlYiIe5dasJ2S8NlBZu2UU3zaUpNnB7viYDB6*wfFlgtopn/WdbXW0Yhik3hj8nDreEmaK12To8qfAJx2ooq43i0wBIL*0Jkba*QpHIprSajrhnCg1PjOLMP37sEauJUwXJaoDR/PPQYIxTFE5kf8xzGlJmqiGejD*Y8R3ewU9yIrxkdQ0S//LCdacULt2QvS/I3APo/j0FAgSCOU3SBLdDL6UBPD4fLeEzo7uUIW8gUMThzZX*u2iUuNwJdqWC2NsFtWkUWt03sz3xYQpR8pLA4vrsUmldzUMWe8</FPData>
<Address>beed</Address>
<ContactNo>5745745747</ContactNo>
</FingerPrintUserDetails>
</content>
C#:
XmlDocument doc = new XmlDocument();
doc.Load("E://BioEnable_Project//fp_project_using_xml//fp_project_using_xml//Capture_Data.xml");
XmlElement root = doc.DocumentElement;
XmlNodeList nodes = root.SelectNodes("FPData");
foreach(XmlElement node in nodes)
{
MessageBox.Show(node.Value);
}
I have to check FPData value on each node..i use above code but not getting..

In your XPath, provide the full path to the node.
XmlNodeList nodes = root.SelectNodes("/content/FingerPrintUserDetails/FPData");
What is happening is that there is no direct FPData node under the document root.

XmlNodeList nodes = root.SelectNodes("content/FingerPrintUserDetails");
it will return array of FingerPrintUserDetails, then find FPData in them
XmlNodeList res = nodes[index].SelectNodes("FPData");

Using LINQ to XML:
XDocument doc = XDocument.Load("XmlFilePath");
var selectors = from elements in doc.Elements("content").Elements("FingerPrintUserDetails")
select elements;
foreach (var element in selectors)
{
MessageBox.Show(element.Element("FPData").Value);
}

XmlDocument doc = new XmlDocument();
doc.Load("E://BioEnable_Project//fp_project_using_xml//fp_project_using_xml//Capture_Data.xml");
XmlNodeList lst = doc.GetElementsByTagName("FingerPrintUserDetails");
foreach (XmlElement elem in lst)
{
XmlNode pfData = doc.GetElementsByTagName("FPData")[0];
MessageBox.Show(pfData.Value);
}

Looping through XML Document

My Method:
if (File.Exists( #"C:\config.xml"))
{
System.Xml.XmlDocument xd = new System.Xml.XmlDocument();
xd.Load( #"C:\config.xml");
System.Xml.XmlElement root = xd.DocumentElement;
System.Xml.XmlNodeList nl = root.SelectNodes("/config");
foreach (System.Xml.XmlNode xnode in nl)
{
string name = xnode.Name;
string value = xnode.InnerText;
string nv = name + "|" + value;
Send(nv);
}
My Xml Doc
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<config>
<bla>D</bla>
<def>300</def>
<ttOUT>34000</ttOUT>
<num>3800</num>
<pw>help</pw>
<err>1</err>
....and so on
</config>
Now my method returns the first 2 and nothing else.
What am i doing wrong...

use the System.Xml namespace to avoid long type qualifications ie...
using System.Xml;
Then try something like this..
XmlNodeList nl = xd.SelectNodes("config");
XmlNode root = nl[0];
foreach (XmlNode xnode in root.ChildNodes)
{
string name = xnode.Name;
string value = xnode.InnerText;
string nv = name + "|" + value;
Send(nv);
}
I believe there is something wrong with your method.
a) I don't think SelectNodes should take the /config argument, rather it should take config.
b) After selecting the first (and only - XML files in .Net must have one and only one root node) root node you need to iterate through the ChildNodes of the root.

root is the <config> tag, so I don't understand how root.SelectNodes("/config") should work at all. Use root.Childnodes instead.

Problem in reading XML node with unknown root/parent nodes

I have been trying to read an xml file. I have to extract value of nodes "Date" and "Name", but the problem is, they might appear at any level in XML hierarchy.
So when I try with this code,
XmlDocument doc = new XmlDocument();
doc.Load("test1.xml");
XmlElement root = doc.DocumentElement;
XmlNodeList nodes = root.SelectNodes("//*");
string date;
string name;
foreach (XmlNode node in nodes)
{
date = node["date"].InnerText;
name = node["name"].InnerText;
}
and the XML file is ::
<?xml version="1.0" encoding="utf-8"?>
<root>
<child>
<name>Aravind</name>
<date>12/03/2000</date>
</child>
</root>
the above code errors out, as <name> and <date> are not immediate child Elements of root.
is it possible to assume that parent/root nodes are unknown and just with the name of the nodes, copy the values ??

Depending on the exception you are getting, this may or may not be the exact solution. However, I would definitely check that date and name exist before doing a .InnerText on them.
foreach (XmlNode node in nodes)
{
dateNode = node["date"];
if(dateNode != null)
date = dateNode.InnerText;
// etc.
}

I would read up on XPATH and XPATH for C# to do this more efficiently
http://support.microsoft.com/kb/308333
http://www.w3schools.com/XPath/xpath_syntax.asp
Here's a little method that should allow you to get the innerText easily.
function string GetElementText(string xml, string node)
{
XPathDocument doc = new XPathDocument(xml);
XPathNavigator nav = doc.CreateNavigator();
XPathExpression expr = nav.Compile("//" + node);
XPathNodeIterator iterator = nav.Select(expr);
while (iterator.MoveNext())
{
// return 1st but there could be more
return iterator.Current.Value;
}
}

Try to use LINQ:
string xml = #"<?xml version='1.0' encoding='utf-8'?>
<root>
<date>12/03/2001</date>
<child>
<name>Aravind</name>
<date>12/03/2000</date>
</child>
<name>AS-CII</name>
</root>";
XDocument doc = XDocument.Parse(xml);
foreach (var date in doc.Descendants("date"))
{
Console.WriteLine(date.Value);
}
foreach (var date in doc.Descendants("name"))
{
Console.WriteLine(date.Value);
}
Console.ReadLine();
The Descendants method allows you to get all the elements that have a specified name.