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c# Generate XML document based on Xpath

I need to create an XML document like this:
<Root>
<Data>
<Name>Name1</Name>
<Surname>Surname1</Surname>
<Gender>M</Gender>
</Data>
<Data>
<Name>Name2</Name>
<Surname>Surname2</Surname>
<Gender>F</Gender>
</Data>
</Root>
I've got the Xpath of the XML Elements, so I've create the following class
class XpathFieldValue
{
public string Xpath { get; set; }
public string Value { get; set; }
}
and then the following method
public static void CreateXml()
{
List<XpathFieldValue> fieldValues = new List<XpathFieldValue> {
new XpathFieldValue{ Xpath="/Root/Data/Name", Value="Name1" },
new XpathFieldValue{ Xpath="/Root/Data/Surname", Value="Surname1" },
new XpathFieldValue{ Xpath="/Root/Data/Gender", Value="M"},
new XpathFieldValue{ Xpath="/Root/Data/Name", Value="Name2" },
new XpathFieldValue{ Xpath="/Root/Data/Surname", Value="Surname2" },
new XpathFieldValue{ Xpath="/Root/Data/Gender", Value="F"}
};
XmlDocument document = new XmlDocument();
document.LoadXml("<Root/>");
foreach (XpathFieldValue fieldValue in fieldValues)
{
Set(document, fieldValue.Xpath, fieldValue.Value);
}
document.Save(#"C:\Temp\xmlDocOut.xml");
}
I've copyed the Set method from here: link
But when I run it it creates only the last parth of XML
<Root>
<Data>
<Name>Name2</Name>
<Surname>Surname2</Surname>
<Gender>F</Gender>
</Data>
</Root>
Can anyone help me?

XPath isn't really intended to generate documents but to access em.
Another (probably better) approach would be to serialize it.
But, since the question requires the fields of xml to be variable, serialization isn't a viable way. i STRONGLY advise you to change this requirement and you'll see why in the following example:
using System;
namespace ConsoleApp1
{
class Program
{
static void Main(string[] args)
{
using (var writer = new System.IO.StreamWriter(#"C:\Users\luigi.trabacchin\Desktop\asd.xml"))
{
var doc = new System.Xml.XmlDocument();
var root = doc.CreateElement("Root");
doc.AppendChild(root);
for (var i = 0; i <= 1; i++)
{
var dataNode = doc.CreateElement("Data");
root.AppendChild(dataNode);
{
var node = doc.CreateElement("Name");
dataNode.AppendChild(node);
var text = doc.CreateTextNode($"Name {i}");
node.AppendChild(text);
}
{
var node = doc.CreateElement("Surname");
dataNode.AppendChild(node);
var text = doc.CreateTextNode($"Surname {i}");
node.AppendChild(text);
}
{
var node = doc.CreateElement("Gender");
dataNode.AppendChild(node);
var text = doc.CreateTextNode(i %2 == 0 ? "M" : "F");
node.AppendChild(text);
}
}
doc.Save(writer);
}
Console.WriteLine("Hello World!");
}
}
}
It quickly becomes very tedious and hard to work with.
Still i hope this answer your question.
Next time, maybe, state all the requirements directly in the question!

How would I parse an XML file into a list

List:
List<string> list = new List<string>();
XML File:
<memberlist>
<member>
<name>Name</name>
<status>Status</status>
</member>
</memberlist>
How would I go about parsing this file, lets say (file.xml) into the list?
I've tried many ways but none of them seem to be working.
I want to check to see if the status is 'gold', and if it is, I would like to put the name of that member into the list.

Load the xml into an XDocument. You can do this from a file, I have demonstrated from a string.
Do a linq query for elements named "status" (within "member") that also have a value of "gold".
Of those, grab the value of the "name" element.
Use AddRange on your list of strings.
List<string> lstGolds = new List<string>();
string xml ="<memberlist><member><name>Name</name><status>gold</status></member></memberlist>";
XDocument doc = XDocument.Parse(xml);
var goldStatus = doc.Descendants("member")
.Where(d => d.Element("status").Value == "gold")
.Select(d => d.Element("name").Value);
lstGolds.AddRange(goldStatus);

You should use using System.Xml.Linq;
using (FileStream fileStramWrite = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
using (StreamReader streamReader = new StreamReader(fileStramWrite))
{
var xdoc = XDocument.Load(streamReader);
var xElement = xdoc.Element("memberlist");
var xElement2 = xElement.Element("member");
var name = xElement2.Element("name").Value;
var status = xElement2.Element("status").Value;
}

Convert your XML to a list of objects....
Use these two mehods:
public static string Serialize<T>(T dataToSerialize)
{
try
{
var stringwriter = new ISOEncodingStringWriter();
var serializer = new XmlSerializer(typeof(T));
var xns = new XmlSerializerNamespaces();
xns.Add(string.Empty, string.Empty);
serializer.Serialize(stringwriter, dataToSerialize, xns);
return stringwriter.ToString();
}
catch
{
throw;
}
}
public static T Deserialize<T>(string xmlText)
{
try
{
var stringReader = new System.IO.StringReader(xmlText);
var serializer = new XmlSerializer(typeof(T));
return (T)serializer.Deserialize(stringReader);
}
catch
{
throw;
}
}
Make the following Class where you give the following attributes
[XmlRoot(ElementName = "Members", Namespace = "")]
public class Members
{
[XmlElement("Member")]
public Member[] member { get; set; }
}
public class Member
{
[XmlElementAttribute("Name")]
public string Name { get; set; }
[XmlElementAttribute("Status")]
public string Status { get; set; }
}
Then deserialize your data.
Members result = Deserialize<Members>(XML_String);
You got your members in a array and you ca convert that to a list if you want.

You can use LINQ
XElement xml = XElement.Load("locationToYourXmlFile");
var members = xml.Elements("member");
var list = members.Where(member => member.Element("status")?.Value == "Gold")
.Select(member => member.Element("name")?.Value)
.ToList();
Assuming your XML has a bunch of member elements under the root memberlist element, each with a name and status element inside that.
<?xml version="1.0" encoding="utf-8"?>
<memberlist>
<member>
<name>John</name>
<status>Gold</status>
</member>
<member>
<name>Sam</name>
<status>Silver</status>
</member>
<member>
<name>Sara</name>
<status>Gold</status>
</member>
</memberlist>

Serialize a list of primitives to XML with overrides

I'm trying to serialize an array of integers to XML, but I can't quite get the output to look the way I want. I need to find some way to override the element name of each element in the array.
The code I have so far:
var numbers = new int[]{1, 2, 3, 4, 5};
var serializer = new XmlSerializer(typeof(int[]), new XmlRootAttribute("rows"));
using (var stringWriter = new StringWriter())
{
serializer.Serialize(stringWriter, numbers);
Console.Write(stringWriter.ToString());
}
The output I am after:
<?xml version="1.0" encoding="utf-16"?>
<rows xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<row>1</row>
<row>2</row>
<row>3</row>
<row>4</row>
<row>5</row>
</rows>
The current output that I see:
<?xml version="1.0" encoding="utf-16"?>
<rows xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<int>1</int>
<int>2</int>
<int>3</int>
<int>4</int>
<int>5</int>
</rows>

You can create a seperate class to hold your values and you can specify Xml attributes as follows:
[Serializable]
[XmlRoot("rows")]
public class Rows
{
[XmlElement("row")]
public List<int> Elements { get; set; }
}
public static void SerializeOnScreen()
{
Rows numbers = new Rows();
numbers.Elements = new List<int>() { 1, 2, 3, 4, 5 };
var serializer = new XmlSerializer(typeof(Rows));
using (var stringWriter = new StringWriter())
{
serializer.Serialize(stringWriter, numbers);
Console.Write(stringWriter.ToString());
}
}

parsing xml and my code got ugly, any more elegant way to do this?

I have the following XML:
<propertyMetrics month="12" year="2003" propertyId="3923837">
<metric name="siteTotal" uom="kBtu" dataType="numeric">
<value>241609.4</value>
</metric>
<metric name="waterUseTotal" dataType="numeric">
<value xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nil="true"/>
</metric>
<metric name="propGrossFloorArea" uom="ft²" dataType="numeric">
<value>20429</value>
</metric>
<metric name="totalGHGEmissions" uom="MtCO2e" dataType="numeric">
<value>21.2</value>
</metric>
<metric name="greenPowerOnSite" dataType="numeric">
<value xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nil="true"/>
</metric>
<metric name="energyBaselineDate" dataType="date">
<value>2010-12-31</value>
</metric>
<metric name="score" dataType="numeric">
<value xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nil="true"/>
</metric>
I am trying to associate the "name" attribute with the "value" element and the "uom" attribute if it exists.
I originally did this:
var propMetrics = doc.Descendants("metric")
.Where(e => !string.IsNullOrEmpty(e.Element("value").Value))
.ToDictionary(e => e.Attribute("name").Value, e => new { uom = e.Attribute("uom").Value, value =(double) e.Element("value") });
This fails when there is no "uom" attribute. So now I make two LIQN calls and have this much uglier looking code:
var propMetrics = doc.Descendants("metric")
.Where(e => !string.IsNullOrEmpty(e.Element("value").Value) && !(e.FirstAttribute.Value == "energyBaselineDate") && !(e.FirstAttribute.Value == "score"))
.ToDictionary(e => e.Attribute("name").Value,
e => new
{
uom = e.Attribute("uom").Value,
value = (double)e.Element("value")
});
foreach(var x in propMetrics)
{
builder.Append(x.Key + ": " + x.Value.value + "<br>\n" + "uom: " + x.Value.uom + "<br>\n");
}
var score = doc.Descendants("metric")
.Where(e => !string.IsNullOrEmpty(e.Element("value").Value) && (e.FirstAttribute.Value == "energyBaselineDate") || (e.FirstAttribute.Value == "score"))
.Select(e => new {
name = e.Attribute("name").Value,
value = (string)e.Element("value")});
foreach(var x in score)
{
builder.Append(x.name + ": " + x.value + "<br>\n");
}
Is there a simple way to do this? Possibly inside of a single LINQ query?

I would like to suggest that doing complex reading and editing of xml would be far easier using a serialization model. You can easily transform your xml into c# objects, and then edit the object properties however you like. Turning your xml into objects can be done as easily as this:
static List<Metric> DeserializeFromXML(string xmlString)
{
XmlSerializer deserializer = new XmlSerializer(typeof(List<Metric>));
List<Metric> metrics;
metrics = (List<Metric>)deserializer.Deserialize(xmlString);
return metrics;
}
Likewise, you could turn your objects back into xml using the following:
static public string SerializeToXML(List<Metric> metrics)
{
XmlSerializer serializer = new XmlSerializer(typeof(List<Metric>));
using (StringWriter writer = new StringWriter())
{
serializer.Serialize(writer, metrics);
return writer.ToString();
}
}
Based on the xml you provided, it looks like your c# Metric object that you will use to serialize in and out of should look something like this:
public class Metric
{
public string name { get; set; }
public string uom { get; set; }
public string dataType { get; set; }
public string value { get; set; }
}

var propMetrics = (
from e in doc.Descendants( "metric" )
where !string.IsNullOrEmpty( e.Element( "value" ).Value )
let auom = e.Attribute( "uom" )
select new {
key = e.Attribute( "name" ).Value,
value = new {
value = (double)e.Element( "value" ),
uom = auom != null ? auom.Value : ""
}
} ).ToDictionary( p => p.key, p => p.value );

Deserialize to list

i am using the XmlSerializer.Serialize and XmlSerializer.Deserialize
i have a class MetricResult:
public class Metricresult
{
public string metric;
public string newvalue;
public string deltavalue;
}
and i am calculating some results that will be stored in :
List<Metricresult> metricresults = new List<Metricresult>();
i changed this list to xml file succefully and in an other project i need to deserialize this list but there is an exception thrown :
there-is-an-error-in-xml-document-0-0-during-deserialization
the xml File
<?xml version="1.0" encoding="utf-8"?>
<ArrayOfMetricresult xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<Metricresult>
<metric>numberofdeclaration</metric>
<newvalue>0</newvalue>
<deltavalue>0</deltavalue>
</Metricresult>
<Metricresult>
<metric>numberofdeclaration</metric>
<newvalue>0</newvalue>
<deltavalue>0</deltavalue>
</Metricresult>
<Metricresult>
<metric>numberofdeclaration</metric>
<newvalue>0</newvalue>
<deltavalue>0</deltavalue>
</Metricresult>
<Metricresult>
<metric>numberofdeclaration</metric>
<newvalue>0</newvalue>
<deltavalue>0</deltavalue>
</Metricresult>
<Metricresult>
<metric>numberofdeclaration</metric>
<newvalue>0</newvalue>
<deltavalue>0</deltavalue>
</Metricresult>
<Metricresult>
<metric>numberofdeclaration</metric>
<newvalue>0</newvalue>
<deltavalue>0</deltavalue>
</Metricresult>
</ArrayOfMetricresult>

Weird, coz the following works perfectly fine for me:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml;
using System.Xml.Serialization;
public class MetricResult
{
public string Metric { get; set; }
public string NewValue { get; set; }
public string DeltaValue { get; set; }
}
class Program
{
static void Main()
{
// define some metric results to serialize
var metricResults = new[]
{
new MetricResult { Metric = "metric 1", NewValue = "new value 1", DeltaValue = "delta 1" },
new MetricResult { Metric = "metric 2", NewValue = "new value 2", DeltaValue = "delta 2" },
new MetricResult { Metric = "metric 3", NewValue = "new value 3", DeltaValue = "delta 3" },
}.ToList();
var serializer = new XmlSerializer(metricResults.GetType());
using (var writer = XmlWriter.Create("metrics.xml"))
{
// serialize the metric results we defined previously to metrics.xml
serializer.Serialize(writer, metricResults);
}
using (var reader = XmlReader.Create("metrics.xml"))
{
// read metrics.xml and deserialize back
metricResults = (List<MetricResult>)serializer.Deserialize(reader);
foreach (var result in metricResults)
{
Console.WriteLine("metric: {0}, new value: {1}, delta: {2}", result.Metric, result.NewValue, result.DeltaValue);
}
}
}
}
and metrics.xml looks as expected:
<?xml version="1.0" encoding="utf-8"?>
<ArrayOfMetricResult xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<MetricResult>
<Metric>metric 1</Metric>
<NewValue>new value 1</NewValue>
<DeltaValue>delta 1</DeltaValue>
</MetricResult>
<MetricResult>
<Metric>metric 2</Metric>
<NewValue>new value 2</NewValue>
<DeltaValue>delta 2</DeltaValue>
</MetricResult>
<MetricResult>
<Metric>metric 3</Metric>
<NewValue>new value 3</NewValue>
<DeltaValue>delta 3</DeltaValue>
</MetricResult>
</ArrayOfMetricResult>

An error at 0,0 usually means you have whitespace at the start of your xml file, before the first element. Look carefully at the xml (perhaps looking at the binary, rather than the text - it could also be a unicode invisible space, etc).
Also: whenever using XmlSerializer, look at the InnerExceptions:
catch(Exception ex) {
while(ex != null) {
Trace.WriteLine(ex.Message);
ex = ex.InnerException;
}
}
there are usually very detailed explanations, if you look all the way through the messages.
One very common error people make is when using streams, not rewinding them. The following will error with a 0,0 error:
using (var ms = new MemoryStream())
{
serializer.Serialize(ms, metricResults);
serializer.Deserialize(ms);
}
because the serialize left the stream at the end. If you have code like this, reset the stream to the start (ms.Position = 0;) between serialize and deserialize. See also: How many ways can you mess up IO?