I want to read specific data from an XML file.
This is what I have come up with so far:
When I run my program without the (if (reader.Name == ControlID)) line reader.Value returns the right value,but when I include the if clause,it returns null
public void GetValue(string ControlID)
{
XmlTextReader reader = new System.Xml.XmlTextReader("D:\\k.xml");
string contents = "";
while (reader.Read())
{
reader.MoveToContent();
if (reader.Name == ControlID)
contents = reader.Value;
}
}
Go through following code:
XmlDocument doc = new XmlDocument();
doc.Load(filename);
string xpath = "/Path/.../config"
foreach (XmlElement elm in doc.SelectNodes(xpath))
{
Console.WriteLine(elm.GetAttribute("id"), elm.GetAttribute("desc"));
}
Using XPathDocument (faster, smaller memory footprint, read-only, weird API):
XPathDocument doc = new XPathDocument(filename);
string xpath = "/PathMasks/Mask[#desc='Mask_X1']/config"
XPathNodeIterator iter = doc.CreateNavigator().Select(xpath);
while (iter.MoveNext())
{
Console.WriteLine(iter.Current.GetAttribute("id"), iter.Current.GetAttribute("desc'));
}
Can also refer this link:
http://support.microsoft.com/kb/307548
This might be helpful to you.
You can try the following code for example xPath query:
XmlDocument doc = new XmlDocument();
doc.Load("k.xml");
XmlNode absoluteNode;
/*
*<?xml version="1.0" encoding="UTF-8"?>
<ParentNode>
<InfoNode>
<ChildNodeProperty>0</ChildNodeProperty>
<ChildNodeProperty>Zero</ChildNodeProperty>
</InfoNode>
<InfoNode>
<ChildNodeProperty>1</ChildNodeProperty>
<ChildNodeProperty>One</ChildNodeProperty>
</InfoNode>
</ParentNode>
*/
int parser = 0
string nodeQuery = "//InfoNode//ChildNodeProperty[text()=" + parser + "]";
absoluteNode = doc.DocumentElement.SelectSingleNode(nodeQuery).ParentNode;
//return value is "Zero" as string
var nodeValue = absoluteNode.ChildNodes[1].InnerText;
Related
in this xml
<Roots>
<Root Name="cab">element_list</Root>
</Roots>
I want to get the value of attribute Name which is cab and element_list
I have this code
XmlDocument doc = new XmlDocument();
doc.LoadXml("<Root Name=\"cab\">element_list</Root>");
XmlElement root = doc.DocumentElement;
var values = doc.Descendants("Roots").Select(x => new { Name = (string)x.Attribute("Name"), List = (string)x }).ToList();
What I get when I run the debugger is
values> Name = "null", List = "element_list"
I am not understanding why I am getting a null value when I should be getting cab for the attribute Name
XDocument is much easier to work with compared to XmlDocument. Perhaps consider switching to it?
public static void ParseXml()
{
string str = "<Roots><Root Name=\"cab\">element_list</Root></Roots>";
using TextReader textReader = new StringReader(str);
XDocument doc = XDocument.Load(textReader);
var val = doc.Element("Roots").Element("Root").Attribute("Name").Value;
}
xml file-> for example this is hosted on the url http://localhost/test1
<?xml version="1.0" encoding="utf-8"?>
<MSG>
<arabic>
<translationOne>اول</translationOne>
<translationTwo>دوم</translationTwo>
</arabic>
<persian>
<translationOne>یک</translationOne>
<translationTwo>دوم</translationTwo>
</persian>
</MSG>
c# class
var m_strFilePath = "http://localhost/test1";
string xmlStr;
using (var wc = new WebClient())
{
xmlStr = wc.DownloadString(m_strFilePath);
}
var xmldoc = new XmlDocument();
xmldoc.LoadXml(xmlStr);
XmlNodeList unNodeA = xmldoc.SelectNodes("MSG/arabic");
XmlNodeList unNodeP = xmldoc.SelectNodes("MSG/persian");
string arabic = "";
foreach (XmlNode i in unNodeA)
{
arabic += i["translationOne"].InnerText;
}
string persian= "";
string persian2 ="";
foreach (XmlNode ii in unNodeP)
{
persian+= ii["translationOne"].InnerText;
persian2+= ii["translationTwo"].InnerText;
}
->>print(arabic and persian);
here the test contain not correct format like (اول دوم) it's some kind of (عبد العزيز عباسین)
It is better to use LINQ to XML API. It is available in the .Net Framework since 2007.
c#
void Main()
{
XDocument xdoc = XDocument.Parse(#"<?xml version='1.0' encoding='utf-8'?><MSG>
<arabic>
<translationOne>اول</translationOne>
<translationTwo>دوم</translationTwo>
</arabic>
<persian>
<translationOne>یک</translationOne>
<translationTwo>دوم</translationTwo>
</persian>
</MSG>");
foreach (XElement elem in xdoc.Descendants("arabic").Elements())
{
Console.WriteLine("translation: {0}", elem.Value);
}
}
If you need to load XML from the URL:
const string Url = #"http://hurt.super-toys.pl/xml/super_toys_ceneo_pelny.xml";
XDocument xdoc = XDocument.Load(Url);
Output
translation: اول
translation: دوم
I'm trying to read an element from my xml file.
I need to read an string in an "link" element inside the "metadata",
but there are 2 elements called "link", I only need the second one:
<metadata>
<name>visit-2015-02-18.gpx</name>
<desc>February 18, 2015. Corn</desc>
<author>
<name>text</name>
<link href="http://snow.traceup.com/me?id=397760"/>
</author>
<link href="http://snow.traceup.com/stats/u?uId=397760&vId=1196854"/>
<keywords>Trace, text</keywords>
I need to read this line:
<link href="http://snow.traceup.com/stats/u?uId=397760&vId=1196854"/>
This is the working code for the first "link" tag, it works fine,
public string GetID(string path)
{
string id = "";
XmlReader reader = XmlReader.Create(path);
while (reader.Read())
{
if ((reader.NodeType == XmlNodeType.Element) && (reader.Name == "link"))
{
if (reader.HasAttributes)
{
id = reader.GetAttribute("href");
MessageBox.Show(id + "= first id");
return id;
//id = reader.ReadElementContentAsString();
}
}
}
return id;
}
Does anyone know how I can skip the first "link" element?
or check if reader.ReadElementContentAsString() contains "Vid" or something like that?
I hope you can help me.
xpath is the answer :)
XmlReader reader = XmlReader.Create(path);
XmlDocument doc = new XmlDocument();
doc.Load(reader);
XmlNodeList nodes = doc.SelectNodes("metadata/link");
foreach(XmlNode node in nodes)
Console.WriteLine(node.Attributes["href"].Value);
Use the String.Contains method to check if the string contains the desired substring, in this case vId:
public string GetID(string path)
{
XmlReader reader = XmlReader.Create(path);
while (reader.Read())
{
if ((reader.NodeType == XmlNodeType.Element) && (reader.Name == "link"))
{
if (reader.HasAttributes)
{
var id = reader.GetAttribute("href");
if (id.Contains(#"&vId"))
{
MessageBox.Show(id + "= correct id");
return id;
}
}
}
return String.Empty;
}
If acceptable you can also use LINQ2XML:
var reader = XDocument.Load(path); // or XDocument.Parse(path);
// take the outer link
Console.WriteLine(reader.Root.Element("link").Attribute("href").Value);
The output is always:
http://snow.traceup.com/stats/u?uId=397760&vId=1196854= first id
Another options is to use XPath like #user5507337 suggested.
XDocument example:
var xml = XDocument.Load(path); //assuming path points to file
var nodes = xml.Root.Elements("link");
foreach(var node in nodes)
{
var href = node.Attribute("href").Value;
}
I want to update the xml document and i need to return the updated xml in string. I am trying like below. when i save the document it expects the file name. but i dont want to save this as file. i just want to get the updated xml in string.
string OldXml = #"<Root>
<Childs>
<first>this is first</first>
<second>this is second </second>
</Childs
</Root>";
XmlDocument NewXml = new XmlDocument();
NewXml.LoadXml(OldXml );
XmlNode root = NewXml.DocumentElement;
XmlNodeList allnodes = root.SelectNodes("*");
foreach (XmlNode eachnode in allnodes)
{
if (eachnode.Name == "first")
{
eachnode.InnerText = "1";
}
}
NewXml.Save();
string newxml = NewXml.OuterXml;
You don't need to call Save method because string is immutable, your problem is in root.SelectNodes("*"), it just get child nodes, not all level of nodes. You need to go one more level:
foreach (XmlNode eachnode in allnodes)
{
var firstNode = eachnode.ChildNodes.Cast<XmlNode>()
.SingleOrDefault(node => node.Name == "first");
if (firstNode != null)
{
firstNode.InnerText = "1";
}
}
string newxml = NewXml.OuterXml;
It would be strongly recommended using LINQ to XML, it's simpler:
var xDoc = XDocument.Parse(OldXml);
foreach (var element in xDoc.Descendants("first"))
element.SetValue(1);
string newXml = xDoc.ToString();
Your iteration never reaches a node called "first". Else it would work fine without saving the NewXml.
You could however use a XElement and iterate over all descendants.
string OldXml = #"<Root>
<Childs>
<first>this is first</first>
<second>this is second </second>
</Childs>
</Root>";
var NewXml = XElement.Parse(OldXml);
foreach (var node in NewXml.Descendants())
{
if (node.Name.LocalName == "first")
{
node.Value = "1";
}
}
var reader = NewXml.CreateReader();
reader.MoveToContent();
string newxml = reader.ReadInnerXml();
How I can make following query
If I have XmlDocument and it may have following xml
<EquipmentParameterModified dateTime="2011-04-06T12:03:10.00+01:00" parameter="ExtApp">
<Extensions ParameterId="External App Interface" FromParameterValue="" ToParameterValue="DISABLED"/>
</EquipmentParameterModified>
How I can check that I have EquipmentParameterModified and take values of ParameterId and ToParameterValue
Thanks for help.
XmlDocument xmldoc = new XmlDocument();
xmldoc.Load(new StringReader(xmlstr));
XmlNode node = xmldoc.GetElementsByTagName("Extensions").Item(0);
string id = node.Attributes["ParameterId"].Value;
string val = node.Attributes["ToParameterValue"].Value;
Are you trying to find the element given the 2 input search values? What do you want your output to be? If you just want to see that you have a matching element, this code should do the trick:
If yes, try something like this:
public static void Main()
{
var paramId = "External App Interface";
var toParameterValue = "DISABLED";
var xdoc = XDocument.Parse(#"
<EquipmentParameterModified dateTime='2011-04-06T12:03:10.00+01:00' parameter='ExtApp'>
<Extensions ParameterId='External App Interface' FromParameterValue='' ToParameterValue='DISABLED'/>
</EquipmentParameterModified>");
var ret = xdoc.Root
.Elements("Extensions")
.Where(e => e.Attribute("ParameterId").Value == paramId &&
e.Attribute("ToParameterValue").Value == toParameterValue)
.FirstOrDefault();
if (ret != null)
Console.WriteLine(ret.Name);
}
Update for .NET 2.0 & XmlDocument:
public static void Main()
{
var paramId = "External App Interface";
var toParameterValue = "DISABLED";
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.LoadXml(#"
<EquipmentParameterModified dateTime='2011-04-06T12:03:10.00+01:00' parameter='ExtApp'>
<Extensions ParameterId='External App Interface' FromParameterValue='' ToParameterValue='DISABLED'/>
</EquipmentParameterModified>");
XmlNode node = xmlDoc.GetElementsByTagName("Extensions")[0];
if (node.Attributes["ParameterId"].Value == paramId &&
node.Attributes["ToParameterValue"].Value == toParameterValue)
{
Console.WriteLine("Found matching node:" + node.Name);
return;
}
}
I recommend using XPath to get the element you're aiming for, do a null check, then get specific attributes of that element, doing a null check on the attribute value before calling the .Value property.