I have an XML file
<Person>
<PersonItem id="0">
<Time>1/8/2014</Time>
<Step><![CDATA[Normal]]></Step>
<HasAddress/>
<Address/>
</PersonItem>
<PersonItem id="1">
<Time>1/8/2014 3:21:45 PM</Time>
<Step><![CDATA[Normal]]></Step>
<HasAddress/>
<Address/>
</PersonItem>
<PersonItem id="2">
<Time>1/8/2014</Time>
<Step><![CDATA[Normal]]></Step>
<HasAddress>Main</HasAddress>
<Address>
<AddressItem id="0" location=5>
<Address>15 Oak</Address>
</AddressItem>
<AddressItem id="1" location=7>
<Address>12 Maple</Address>
</AddressItem>
<AddressItem id="2" location=8>
<Address>30 Beech</Picture>
</AddressItem>
</Address>
</PersonItem>
</Person>
I want to put to retrieve the information and send some of it to a database. I've tried several different ways of dealing with this and I believe I'm close. Here is the Linq I tried.
public void DoIt(fileName)
{
XElement xml = XElement.Load(fileName);
var items = from item in xml.Elements("PersonItem")
where (from x in item.Elements("HasAddress")
where x.Element("HasAddress") != null
select x).Any()
select item;
Array.ForEach(items.ToArray(),
o=>Console.WriteLine(o.Element("Time").Value));
Console.ReadLine();
}
The problem is nothing is being returned.
Could be just a typo but in your xml file there is this tag error.
<Address>30 Beech</Picture>
which should be:
<Address>30 Beech</Address>
Try this:
XElement xml = XElement.Load(fileName);
var items = xml.Descendants("PersonItem")
.Where(x => (string)x.Element("HasAddress") != null)
.Select(x => x);
XDocument xml = XDocument.Load("Input.xml");
var items = from item in xml.Root.Elements("PersonItem")
where !string.IsNullOrEmpty((string)item.Element("HasAddress"))
select item;
For your sample XML document returns only the last PersonItem element.
Related
I have the following problem, I want to select the book with the author "Johnny Dapp33", which unfortunately does not work.
XML Code:
<employees xmlns:bar="http://www.bar.org">
<employee id="Test1">
<name>Johnny Dapp</name>
<author>Al Pacino</author>
</employee>
<employee id="Test2">
<name>Johnny Dapp33</name>
<author>Al Pacino</author>
</employee>
</employees>
I would have tried it via ".SelectSingleNode", unfortunately I always fail with the XPath.
Thank you for your help!
Let's say we have a file called Employees.xml in our project directory.
We can load the xml file in our memory by using this assignment:
XmlDocument doc = new XmlDocument();
doc.Load("Employees.xml");
Second we try to find a single node (presuambly) by its id in a structure employees/employee (this is our path), no we have to add the search param (id in this case) like this:
XmlNode singleNode = doc.SelectSingleNode("/employees/employee[#id='Test1']");
Console.WriteLine(singleNode.OuterXml);
However if we only know the name we are looking for we can also search for that specific value like this. We search in the employee node for the node value of name with the value of Johnny Dapp33:
XmlNode singleNode = doc.SelectSingleNode("descendant::employee[name='Johnny Dapp33']");
Console.WriteLine(singleNode.OuterXml);
While dealing with XMl, it is better to use LINQ to XML API.
It is available in the .Net Framework since 2007.
c#
void Main()
{
const string filePath = #"e:\Temp\WizardZZ.xml";
XDocument xdoc = XDocument.Load(filePath);
var employee = xdoc.Descendants("employee")
.Where(d => d.Elements("name").FirstOrDefault().Value.Equals("Johnny Dapp33"));
Console.WriteLine(employee);
}
Output
<employee id="Test2">
<name>Johnny Dapp33</name>
<author>Al Pacino</author>
</employee>
If you need to use XPath (and there must be a very strong reason for it), you can use it with XElement:
var xml = """
<employees xmlns:bar="http://www.bar.org">
<employee id="Test1">
<name>Johnny Dapp</name>
<author>Al Pacino</author>
</employee>
<employee id="Test2">
<name>Johnny Dapp33</name>
<author>Al Pacino</author>
</employee>
</employees>
""";
var x = XElement.Parse(xml);
var employees = x.XPathSelectElements("/employee[name='Johnny Dapp33']");
if (employees is not null)
{
foreach (var employee in employees)
{
WriteLine((string)employee.Element("name") ?? "[name] not found");
}
}
else
{
WriteLine("did not find any employees");
}
I'm trying to use LINQ in a .Net application to filter out personal data from the XML I save to a database.
Sample XML
<?xml version="1.0" encoding="UTF-8"?>
<body>
<Details>
<Id>1</Id>
<objectList>
<object>
<Key>Account</Key>
<Value>12345</Value>
</object>
<object>
<Key>Password</Key>
<Value>abcd</Value>
</object>
</objectList>
</Details>
</Body>
What I have working:
var xmlFile = File.ReadAllText("Test.xml");
var xDoc = XDocument.Parse(xmlFile);
var newXDoc = xDoc.Descendants().Where(e => e.Name.LocalName == "Value").ToList().ForEach(e => e.Value = "FILTERED");
However, this filters the value you for all objects.
What I'm looking to do is a filter the value for specific objects only, say, where Key equals "Password"
Is there a way to do this?
You can do the following:
var objectValue="Password";
var result= xDoc.Descendants("object").Where(e => e.Element("Key").Value==objectValue);
foreach(var e in result)
{
e.Element("Value").Value = "FILTERED";
}
First filter the objects according to the condition you want to apply and then change the value of the Value node as I show above.
<test>
<acc id="1"> acc1 </acc>
<acc id="2"> acc2 </acc>
<acc id="3"> acc3 </acc>
<acc id="4"> acc4 </acc>
</test>
For example, if I want to take the value of each <acc> element:
var iAccs = xdoc.Descendants("test").Elements("acc").Select(p => p.Value);
List<string> myList = new List<string>();
foreach(string p in iAccs)
{
myList.Add(p);
}
But how to substract all the attribute "id" values of each <acc> elements?
You can easily get this using LINQ-to-XML:-
XDocument xdoc = XDocument.Load(#"You XML file path");
List<string> result = xdoc.Descendants("acc")
.Select(x => (string)x.Attribute("id")).ToList();
Or if you prefer query syntax then:-
List<int> result2 = (from x in xdoc.Descendants("acc")
select (int)x.Attribute("id")).ToList();
<?xml version="1.0" encoding="UTF-8"?>
<Envelope xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<Message>
<MessageID>1</MessageID>
<Product>
<SKU>33333-01</SKU>
</Product>
</Message>
</Envelope>
I've tried googling but whether I'm just not providing the correct search criteria I don't know.
I want to be able to search the XML file based on the MessageID and then grab the SKU.
I then want to search another XML file based on the SKU and remove that message completely.
<?xml version="1.0" encoding="UTF-8"?>
<Envelope xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<Message>
<MessageID>1</MessageID>
<Inventory>
<SKU>33333-01</SKU>
<Quantity>1</Quantity>
</Inventory>
</Message>
<Message>
<MessageID>2</MessageID>
<Inventory>
<SKU>22222-01</SKU>
<Quantity>1</Quantity>
</Inventory>
</Message>
</Envelope>
Meaning the XML above becomes:
<?xml version="1.0" encoding="UTF-8"?>
<Envelope xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<Message>
<MessageID>2</MessageID>
<Inventory>
<SKU>22222-01</SKU>
<Quantity>1</Quantity>
</Inventory>
</Message>
</Envelope>
To confirm I cannot confirm that the MessageID will be the same over different XML files.
Thanks in advance for any help.
My questions:
How do I search through XML files?
How do I then grab another Nodes details
Can I remove a complete from an XML file based on a search?
You can use XmlDocument to load your XML document. Then, you can use XPath for searching any nodes.
XmlDocument document = new XmlDocument();
document.Load("C:\fileOnTheDisk.xml");
// or
document.LoadXml("<a>someXmlString</a>");
// Returns single element or null if not found
var singleNode = document.SelectSingleNode("Envelope/Message[MessageID = '1']");
// Returns a NodeList
var nodesList = document.SelectNodes("Envelope/Message[MessageID = '1']");
Read more about XPath at w3schools.com.
Here is a good XPath Tester.
For example, you can use the following XPath to find nodes in your document by ID:
XmlDocument document = new XmlDocument();
document.Load("C:\doc.xml");
var node = document.SelectSingleNode("Envelope/Message[MessageID = '1']");
var sku = node.SelectSingleNode("Inventory/SKU").InnerText;
Console.WriteLine("{0} node has SKU = {1}", 1, sku);
Or you can output all SKUs:
foreach (XmlNode node in document.SelectNodes("Envelope/Message"))
{
Console.WriteLine("{0} node has SKU = {1}",
node.SelectSingleNode("MessageID").InnerText,
node.SelectSingleNode("Inventory/SKU").InnerText);
}
It will produce:
1 node has SKU = 33333-01
2 node has SKU = 22222-01
Note that there are possible NullReferenceExceptions if nodes are not present.
You can simply remove it using RemoveChild() method of its parent.
XmlDocument document = new XmlDocument();
document.Load("C:\doc.xml");
var node = document.SelectSingleNode("Envelope/Message[MessageID = '1']");
node.ParentNode.RemoveChild(node);
document.Save("C:\docNew.xml"); // will be without Message 1
You can use Linq to XML to do this:
var doc= XDocument.Load("input.xml");//path of your xml file in which you want to search based on message id.
var searchNode= doc.Descendants("MessageID").FirstOrDefault(d => d.Value == "1");// It will search message node where its value is 1 and get first of it
if(searchNode!=null)
{
var SKU=searchNode.Parent.Descendants("SKU").FirstOrDefault();
if(SKU!=null)
{
var searchDoc=XDocument.Load("search.xml");//path of xml file where you want to search based on SKU value.
var nodes =searchDoc.Descendants("SKU").Where(d=>d.Value==SKU.Value).Select(d=>d.Parent.Parent).ToList();
nodes.ForEach(node=>node.Remove());
searchDoc.Save("output.xml");//path of output file
}
}
I'd recommend you did this using LINQ to XML - it's much nicer to work with than the old XmlDocument API.
For all the examples, you can parse your XML string xml to an XDocument like so:
var doc = XDocument.Parse(xml);
1. How do I search through XML files?
You can get the SKU for a specific message ID by querying your document:
var sku = (string)doc.Descendants("Message")
.Where(e => (int)e.Element("MessageID") == 1)
.SelectMany(e => e.Descendants("SKU"))
.Single();
2. How do I then grab another Nodes details?
You can get the Message element with a specified SKU using a another query:
var message = doc.Descendants("SKU")
.Where(sku => (string)sku == "33333-01")
.SelectMany(e => e.Ancestors("Message"))
.Single();
3. Can I remove a complete element from an XML file based on a search?
Using your result from step 2, you can simple call Remove:
message.Remove();
Alternatively, you can combine the query from step 2 and simply execute a command to remove any messages that have a specific SKU:
doc.Descendants("SKU")
.Where(sku => (string)sku == "33333-01")
.SelectMany(e => e.Ancestors("Message"))
.Remove();
I tried to answer all your questions:
using System.Xml.XPath;
using System.Xml.Linq;
XDocument xdoc1 = XDocument.Load("xml1.xml");
XDocument xdoc2 = XDocument.Load("xml2.xml");
string sku = String.Empty;
string searchedID = "2";
//1.searching through an xml file based on path
foreach (XElement message in xdoc1.XPathSelectElements("Envelope/Message"))
{
if (message.Element("MessageID").Value.Equals(searchedID))
{
//2.grabbing another node's details
sku = message.XPathSelectElement("Inventory/SKU").Value;
}
}
foreach (XElement message in xdoc2.XPathSelectElements("Envelope/Message"))
{
if (message.XPathSelectElement("Inventory/SKU") != null && message.XPathSelectElement("Inventory/SKU").Value.Equals(sku))
{
//removing a node
message.Remove();
}
}
xdoc2.Save("xml2_del.xml");
}
I would like to filter with high performance XML elements from an XML document.
Take for instance this XML file with contacts:
<?xml version="1.0" encoding="ISO-8859-1"?>
<?xml-stylesheet type="text/xsl" href="asistentes.xslt"?>
<contactlist evento="Cena Navidad 2010" empresa="company">
<contact type="1" id="1">
<name>Name1</name>
<email>xxxx#zzzz.es</email>
<confirmado>SI</confirmado>
</contact>
<contact type="1" id="2">
<name>Name2</name>
<email>xxxxxxxxx#zzzze.es</email>
<confirmado>Sin confirmar</confirmado>
</contact>
</contaclist>
My current code to filter from this XML document:
using System;
using System.Xml.Linq;
class Test
{
static void Main()
{
string xml = #" the xml above";
XDocument doc = XDocument.Parse(xml);
foreach (XElement element in doc.Descendants("contact")) {
Console.WriteLine(element);
var id = element.Attribute("id").Value;
var valor = element.Descendants("confirmado").ToList()[0].Value;
var email = element.Descendants("email").ToList()[0].Value;
var name = element.Descendants("name").ToList()[0].Value;
if (valor.ToString() == "SI") { }
}
}
}
What would be the best way to optimize this code to filter on <confirmado> element content?
var doc = XDocument.Parse(xml);
var query = from contact in doc.Root.Elements("contact")
let confirmado = (string)contact.Element("confirmado")
where confirmado == "SI"
select new
{
Id = (int)contact.Attribute("id"),
Name = (string)contact.Element("name"),
Email = (string)contact.Element("email"),
Valor = confirmado
};
foreach (var contact in query)
{
...
}
Points of interest:
doc.Root.Elements("contact") selects only the <contact> elements in the document root, instead of searching the whole document for <contact> elements.
The XElement.Element method returns the first child element with the given name. No need to convert the child elements to a list and take the first element.
The XElement and XAttribute classes provide a wide selection of convenient conversion operators.
You could use LINQ:
foreach (XElement element in doc.Descendants("contact").Where(c => c.Element("confirmado").Value == "SI"))