i was reading huge xml file of 5GB size by using the following code, and i was success to get the first element Testid but failed to get another element TestMin coming under different namespace
this is the xml i am having
which i am getting as null
.What is wrong here?
EDIT
GMileys answer giving error like The ':' character, hexadecimal value 0x3A, cannot be included in a name
The element es:qRxLevMin is a child element of xn:attributes, but it looks like you are trying to select it as a child of xn:vsDataContainer, it is a grandchild of that element. You could try changing the following:
var dataqrxlevmin = from atts in pin.ElementsAfterSelf(xn + "VsDataContainer")
select new
{
qrxlevmin = (string)atts.Element(es + "qRxLevMin"),
};
To this:
var dataqrxlevmin = from atts in pin.Elements(string.Format("{0}VsDataContainer/{1}attributes", xn, es))
select new
{
qrxlevmin = (string)atts.Element(es + "qRxLevMin"),
};
Note: I changed your string concatenation to use string.Format for readability purposes, either is technically fine to use, but string.Format is a better approach.
What about this approach?
XDocument doc = XDocument.Load(path);
XName utranCellName = XName.Get("UtranCell", "un");
XName qRxLevMinName = XName.Get("qRxLevMin", "es");
var cells = doc.Descendants(utranCellName);
foreach (var cell in cells)
{
string qRxLevMin = cell.Descendants(qRxLevMinName).FirstOrDefault();
// Do something with the value
}
try this code which is very similar to your code but simpler.
using (XmlReader xr = XmlReader.Create(path))
{
xr.MoveToContent();
XNamespace un = xr.LookupNamespace("un");
XNamespace xn = xr.LookupNamespace("xn");
XNamespace es = xr.LookupNamespace("es");
while (!xr.EOF)
{
if(xr.LocalName != "UtranCell")
{
xr.ReadToFollowing("UtranCell", un.NamespaceName);
}
if(!xr.EOF)
{
XElement utranCell = (XElement)XElement.ReadFrom(xr);
}
}
}
actually namespace was the culprit,what i did is first loaded the small section i am getting from.Readform method in to xdocument,then i removed all the namespace,then i took the value .simple :)
Related
I have a xml file:
<?xml version="1.0" encoding="utf-8"?>
<ApplicationConfiguration xmlns="http://test.org/SDK/Configuration.xsd">
<ApplicationName>
<ApplicationUri>123</ApplicationUri>
<ApplicationUri>456</ApplicationUri>
</ApplicationName>
</ApplicationConfiguration>
What I want is set the value of ApplicationUri from 456 to 789 in C# code.
I wrote this code:
string docaddress = "testfile.xml";
XDocument doc = XDocument.Load(docaddress);
doc.Element("ApplicationConfiguration")
.Elements("ApplicationName").FirstOrDefault()
.SetElementValue("ApplicationUri", "789");
doc.Save(docaddress);
The problems are:
There is no error while running. I think the element ApplicationConfiguration is not correct. But when I delete the line xmlns=... from the xml file, it runs normally
The value 789 is replaced with 123, but not 456 as I want (same element name)
Can you tell me how to fix those problems?
Hello and welcome to Stack Overflow!
The xmlns attribute on the ApplicationConfiguration element makes that the root.
So you get the root first. Then you replace the values of each descendant, selecting locally by name with the element name you want. something like this:
string docaddress = "C:\\temp\\testfile.xml";
XDocument doc = XDocument.Load(docaddress);
var root = doc.Root;
var descendants = root.Descendants();
var these = root.Descendants().Where(p => p.Name.LocalName == "ApplicationUri");
foreach (var elem in these)
{
elem.Value = "789";
}
doc.Save(docaddress);
I added namespace to your code :
string docaddress = "testfile.xml";
XDocument doc = XDocument.Load(docaddress);
XNamespace ns = doc.Root.GetDefaultNamespace();
doc.Element(ns + "ApplicationConfiguration")
.Elements(ns + "ApplicationName").FirstOrDefault()
.SetElementValue(ns + "ApplicationUri", "789");
doc.Save(docaddress);
IMHO, here is an easiest method.
It is taking care of the XML default namespace.
No loops. Set based approach.
c#
void Main()
{
const string fileName = #"e:\temp\hala.xml";
const string searchFor = "456";
const string replaceWith = "789";
XDocument doc = XDocument.Load(fileName);
XNamespace ns = doc.Root.GetDefaultNamespace();
// step #1: find element based on the search value
XElement xmlFragment = doc.Descendants(ns + "ApplicationUri")
.Where(d => d.Value.Equals(searchFor)).FirstOrDefault();
// step #2: if found, set its value
if(xmlFragment != null)
xmlFragment.SetValue(replaceWith);
doc.Save(fileName);
}
I'm dealing to access an specific node from a XML Document. I realized that this one as a base namespace. Here is the example.
I'm interested to get the value of the node d:MediaUrl from all descendents node (entry). And I haven't accomplished that.
When I debug the variable iterator 'i', I can see that the XML includes the default namespace again, something like:
<entry xmlns="http://schemas.microsoft.com.ado/..."
And also I have to include the another namespace called 'd'.
What can I do to access to that particular nodes?
This is what I have.
var doc = XDocument.Parse(result);
string BASE_NS = "http://www.w3.org/2005/Atom";
string d = "http://schemas.microsoft.com/ado/2007/08/dataservices";
var query = from i in doc.Descendants(XName.Get("entry", BASE_NS))
select new Image()
{
Url = i.Element(XName.Get("MediaUrl", BASE_NS)).Value
};
var results = query.ToList();
I would suggest using XNamespace rather than XName (personal preference, mainly - as that's how I've always dealt with namespaces in LINQ to XML). To me it's less effort to set up the namespaces in advance and then use Element(NS + "element name") than to useXName.Get(though usingXName.Get` is perfectly fine if that's what you want to do.
If you want to get a all the "MediaUrl" elements for each entry, then I'd do something like this:
XNamespace d = "http://schemas.microsoft.com/ado/2007/08/dataservices";
var query = (from i in doc.Descendants(d + "MediaUrl")
select new Image()
{
Url = i.Value
}).ToList();
If you want to get only one of them, then you need to do something a little different, depending on which one you wanted to get.
For the properties MediaUrl:
XNamespace d = "http://schemas.microsoft.com/ado/2007/08/dataservices";
XNamespace m = "http://schemas.microsoft.com/ado/2007/08/dataservices/metadata";
var query = (from i in doc.Descendants(m + "properties")
select new Image()
{
Url = i.Element(d + "MediaUrl").Value
}).ToList();
For the Thumbnail MediaUrl:
XNamespace d = "http://schemas.microsoft.com/ado/2007/08/dataservices";
var query = (from i in doc.Descendants(d + "Thumbnail")
select new Image()
{
Url = i.Element(d + "MediaUrl").Value
}).ToList();
The key here is to use the namespace in conjunction with the element name in order to retrieve it.
var query = from i in doc.Descendants("{full namespace for prefix d}MediaUrl")
select new Image()
{
Url = i.Value
};
I have a DataGridView control where some values are popluted.
And also I have an xml file. The user can change the value in the Warning Column of DataGridView.And that needs to be saved in the xml file.
The below program just does the job
XDocument xdoc = XDocument.Load(filePath);
//match the record
foreach (var rule in xdoc.Descendants("Rule"))
{
foreach (var row in dgRulesMaster.Rows.Cast<DataGridViewRow>())
{
if (rule.Attribute("id").Value == row.Cells[0].Value.ToString())
{
rule.Attribute("action").Value = row.Cells[3].Value.ToString();
}
}
}
//save the record
xdoc.Save(filePath);
Matching the grid values with the XML document and for the matched values, updating the needed XML attribute.
Is there a better way to code this?
Thanks
You could do something like this:
var rules = dgRulesMaster.Rows.Cast<DataGridViewRow>()
.Select(x => new {
RuleId = x.Cells[0].Value.ToString(),
IsWarning = x.Cells[3].Value.ToString() });
var tuples = from n in xdoc.Descendants("Rule")
from r in rules
where n.Attribute("id").Value == r.RuleId
select new { Node = n, Rule = r };
foreach(var tuple in tuples)
tuple.Node.Attribute("action").Value = tuple.Rule.IsWarning;
This is basically the same, just a bit more LINQ-y. Whether or not this is "better" is debatable. One thing I removed is the conversion of IsWarning first to string, then to int and finally back to string. It now is converted to string once and left that way.
XPath allows you to target nodes in the xml with alot of power. Microsoft's example of using the XPathNavigator to modify an XML file is as follows:
XmlDocument document = new XmlDocument();
document.Load("contosoBooks.xml");
XPathNavigator navigator = document.CreateNavigator();
XmlNamespaceManager manager = new XmlNamespaceManager(navigator.NameTable);
manager.AddNamespace("bk", "http://www.contoso.com/books");
foreach (XPathNavigator nav in navigator.Select("//bk:price", manager))
{
if (nav.Value == "11.99")
{
nav.SetValue("12.99");
}
}
Console.WriteLine(navigator.OuterXml);
Source: http://msdn.microsoft.com/en-us/library/zx28tfx1(v=vs.80).aspx
Considering the following XML:
<Stations>
<Station>
<Code>HT</Code>
<Type>123</Type>
<Names>
<Short>H'bosch</Short>
<Middle>Den Bosch</Middle>
<Long>'s-Hertogenbosch</Long>
</Names>
<Country>NL</Country>
</Station>
</Stations>
There are multiple nodes. I need the value of each node.
I've got the XML from a webpage (http://webservices.ns.nl/ns-api-stations-v2)
Login (--) Pass (--)
Currently i take the XML as a string and parse it to a XDocument.
var xml = XDocument.Parse(xmlString);
foreach (var e in xml.Elements("Long"))
{
var stationName = e.ToString();
}
You can retrieve "Station" nodes using XPath, then get each subsequent child node using more XPath. This example isn't using Linq, which it looks like you possibly are trying to do from your question, but here it is:
XmlDocument xml = new XmlDocument();
xml.Load(xmlStream);
XmlNodeList stations = xml.SelectNodes("//Station");
foreach (XmlNode station in stations)
{
var code = station.SelectSingleNode("Code").InnerXml;
var type = station.SelectSingleNode("Type").InnerXml;
var longName = station.SelectSingleNode("Names/Long").InnerXml;
var blah = "you should get the point by now";
}
NOTE: If your xmlStream variable is a String, rather than a Stream, use xml.LoadXml(xmlStream); for line 2, instead of xml.Load(xmlStream). If this is the case, I would also encourage you to name your variable to be more accurately descriptive of the object you're working with (aka. xmlString).
This will give you all the values of "Long" for every Station element.
var xml = XDocument.Parse(xmlStream);
var longStationNames = xml.Elements("Long").Select(e => e.Value);
Load function is already defined in xmlData class
public class XmlData
{
public void Load(XElement xDoc)
{
var id = xDoc.XPathSelectElements("//ID");
var listIds = xDoc.XPathSelectElements("/Lists//List/ListIDS/ListIDS");
}
}
I'm just calling the Load function from my end.
XmlData aXmlData = new XmlData();
string input, stringXML = "";
TextReader aTextReader = new StreamReader("D:\\test.xml");
while ((input = aTextReader.ReadLine()) != null)
{
stringXML += input;
}
XElement Content = XElement.Parse(stringXML);
aXmlData.Load(Content);
in load function,im getting both id and and listIds as null.
My test.xml contains
<SEARCH>
<ID>11242</ID>
<Lists>
<List CURRENT="true" AGGREGATEDCHANGED="false">
<ListIDS>
<ListID>100567</ListID>
<ListID>100564</ListID>
<ListID>100025</ListID>
<ListID>2</ListID>
<ListID>1</ListID>
</ListIDS>
</List>
</Lists>
</SEARCH>
EDIT: Your sample XML doesn't have an id element in the namespace with the nss alias. It would be <nss:id> in that case, or there'd be a default namespace set up. I've assumed for this answer that in reality the element you're looking for is in the namespace.
Your query is trying to find an element called id at the root level. To find all id elements, you need:
var tempId = xDoc.XPathSelectElements("//nss:id", ns);
... although personally I'd use:
XDocument doc = XDocument.Parse(...);
XNamespace nss = "http://schemas.microsoft.com/SQLServer/reporting/reportdesigner";
// Or use FirstOrDefault(), or whatever...
XElement idElement = doc.Descendants(nss + "id").Single();
(I prefer using the query methods on LINQ to XML types instead of XPath... I find it easier to avoid silly syntax errors etc.)
Your sample code is also unclear as you're using xDoc which hasn't been declared... it helps to write complete examples, ideally including everything required to compile and run as a console app.
I am looking at the question 3 hours after it was submitted and 41 minutes after it was (last) edited.
There are no namespaces defined in the provided XML document.
var listIds = xDoc.XPathSelectElements("/Lists//List/ListIDS/ListIDS");
This XPath expression obviously doesn't select any node from the provided XML document, because the XML document doesn't have a top element named Lists (the name of the actual top element is SEARCH)
var id = xDoc.XPathSelectElements("//ID");
in load function,im getting both id and and listIds as null.
This statement is false, because //ID selects the only element named ID in the provided XML document, thus the value of the C# variable id is non-null. Probably you didn't test thoroughly after editing the XML document.
Most probably the original ID element belonged to some namespace. But now it is in "no namespace" and the XPath expression above does select it.
string xmldocument = "<response xmlns:nss=\"http://schemas.microsoft.com/SQLServer/reporting/reportdesigner\"><action>test</action><id>1</id></response>";
XElement Content = XElement.Parse(xmldocument);
XPathNavigator navigator = Content.CreateNavigator();
XmlNamespaceManager ns = new XmlNamespaceManager(navigator.NameTable);
ns.AddNamespace("nss", "http://schemas.microsoft.com/SQLServer/reporting/reportdesigner");
var tempId = navigator.SelectSingleNode("/id");
The reason for the null value or system returned value is due to the following
var id = xDoc.XPathSelectElements("//ID");
XpathSElectElements is System.xml.linq.XElment which is linq queried date. It cannot be directly outputed as such.
To Get individual first match element
use XPathSelectElement("//ID");
You can check the number of occurrences using XPathSelectElements as
var count=xDoc.XPathSelectElements("//ID").count();
you can also query the linq statement as order by using specific conditions
Inorder to get node value from a list u can use this
foreach (XmlNode xNode in xDoc.SelectNodes("//ListIDS/ListID"))
{
Console.WriteLine(xNode.InnerText);
}
For Second list you havnt got the value since, the XPath for list items is not correct