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How to read specific fields from XML and load into Oracle db

my XML :
- <resources start="0" count="188">-
- <resource classname="Quote">
<field name="name">USD/GEL</field>
<field name="price">2.418900</field>
<field name="symbol">GEL=X</field>
<field name="ts">1488758461</field>
<field name="type">currency</field>
<field name="utctime">2017-03-06T00:01:01+0000</field>
<field name="volume">0</field>
</resource>-
</resources>
C# Code:
var xmlNodes = xElement.Descendants("resource")
.Select(e => new
{
ConvertFrom = e.Attribute("symbol").Value,
ConvRate = e.Attribute("price").Value,
ConvDate = e.Attribute("utctime").Value
});
I tried the above code to fetch and load into oracle but i got a below error.
System.Linq.Enumerable+WhereSelectEnumerableIterator2[System.Xml.Linq.XElement,<>f__AnonymousType03[System.String,System.String,System.String]]
Please help me to resolve this issue.

I think you have misunderstood Attribute method, the name of the attribute is name, symbol is the value, so your query could be this way:
var xmlNodes = xElement.Descendants("resource")
.Select(e => new
{
ConvertFrom = (string)e.Elements().FistOrDefault(r=>r.Attribute("name").Value=="symbol"),
ConvRate = (string)e.Elements().FistOrDefault(r=>r.Attribute("name").Value=="price"),
ConvDate = (DateTime)e.Elements().FistOrDefault(r=>r.Attribute("name").Value=="utctime"),
});

XDocument does not return the expected node

I try to work with the XDocument in C# but have some problems to receive the desired elements. Here is my sample xml
<?xml version="1.0" encoding="UTF-8"?>
<xfdf xmlns="http://ns.adobe.com/xfdf/" xml:space="preserve">
<f href="#{pdffile}"/>
<ids modified="BF43C70442ECB74FA49833BBA44D4679" original="B4870CC046121A41B7D8F0838C87256D"/>
<fields>
<field name="FormInstanceID"><value>#{instanceid}</value></field>
<field name="meta_7"><value>#{meta_7}</value></field>
<field name="meta_6"><value>#{meta_6}</value></field>
<field name="meta_8"><value>#{meta_8}</value></field>
<field name="meta_3"><value>#{meta_3}</value></field>
<field name="meta_2"><value>#{meta_2}</value></field>
<field name="meta_5"><value>#{meta_5}</value></field>
<field name="meta_4"><value>#{meta_4}</value></field>
<field name="meta_1"><value>#{meta_1}</value></field>
<field name="tag_5"><value>#{tag_5}</value></field>
<field name="tag_1"><value>#{tag_1}</value></field>
<field name="tag_2"><value>#{tag_2}</value></field>
<field name="tag_3"><value>#{tag_3}</value></field>
<field name="TAGS"><value>#{TAGS}</value></field>
<field name="tag_4"><value>#{tag_4}</value></field>
<field name="qr"><value>#{qr}</value></field>
<field name="metadata"><value>#{metadata}</value></field>
<field name="pdx.dynform.email"><value>#{pdx.dynform.email}</value></field>
</fields>
</xfdf>
Assuming the given XML I want to extract with XDocument the field values. Currently I do no receive any entry by using this approach
XDocument xfdfData = XDocument.Load(xfdf);
var result = xfdfData.Descendants("fields");
The file is sucessfully loaded in the xfdfData object but the Descendants("fields") does find any nodes.

You don't have a fields element which isn't in a namespace, which is what you're asking for. Due to this in the root element:
xmlns="http://ns.adobe.com/xfdf/"
... the default namespace URI for the descendant nodes is http://ns.adobe.com/xfdf/. So you want:
XNamespace ns = "http://ns.adobe.com/xfdf/";
XDocument doc= XDocument.Load(xfdf);
var result = doc.Descendants(ns + "fields");
Or to find the field elements themselves:
XNamespace ns = "http://ns.adobe.com/xfdf/";
XDocument doc= XDocument.Load(xfdf);
var fields = doc.Descendants(ns + "field");

Getting data from xml with specific data name and value key

I want to get data from xml but there are lots of tags, fields and value keys. I couldn't select the value which I want. How can I select the "Error" value from this XML with C#?
<?xml version="1.0" encoding="UTF-8"?>
<Database xmlns="http://www.example.com/2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<Datas>
<Data name="sMsg" access="private" xsi:type="collection" type="string">
<Value key="Cycle" value="deger1" />
<Value key="Error" value="deger2" />
<Value key="Info" value="deger3" />
<Value key="Jog" />
<Value key="Warning" />
</Data>
<Data name="tTabla" access="private" xsi:type="array" type="tabla" size="1">
<Field name="dddd" xsi:type="array" type="bool" size="1" />
<Field name="ssss" xsi:type="array" type="bool" size="1" />
<Field name="aaaa" xsi:type="array" type="num" size="1" />
<Field name="rrrr" xsi:type="collection" type="num">
<Value key="Actuel" />
<Value key="Expected" />
</Field>
</Data>
</Datas>
</Database>

You can try this way :
var doc = XDocument.Parse(xml);
XNamespace d = doc.Root.GetDefaultNamespace();
var result = (string)
doc.Descendants(d + "Data")
.Elements(d + "Value")
.FirstOrDefault(o => (string) o.Attribute("key") == "Error")
.Attribute("value");
Console.WriteLine(result);

Try this it returns the XElement with Key equal to Error
XDocument m = XDocument.Load(#"Path");
var res = m.Descendants().Where(x => x.Name.LocalName.Equals("Value") && x.Attribute("key") != null && x.Attribute("key").Value.Equals("Error")).FirstOrDefault();

If there are multiple "Error" values for your attributes, you can do:
IEnumerable<XAttribute> answer = xml.Descendants().Attributes().Where(node => node.Value == "Error");
foreach (var xAttribute in answer)
{
Console.WriteLine(xAttribute.Value);
}
If you only want the first or there is only one:
string answer = xml.Descendants().Attributes().FirstOrDefault(node => node.Value == "Error");
Note FirstOrDefault may yield null if it doesn't find any "Error" values inside your xml.
These queries are done using LINQ To XML, i strongly encourage you to read up.

Parsing XML using LINQ in c#

In this xml file (http://www.studiovincent.net/list.xml):
<list version="1.0">
<meta>
<type>resource-list</type>
</meta>
<resources start="0" count="4">
<resource classname="Quote">
<field name="name">Vincent</field>
<field name="username">Hill</field>
<field name="age">31</field>
<field name="hair">black</field>
</resource>
<resource classname="Quote">
<field name="name">John</field>
<field name="username">Tedelon</field>
<field name="age">27</field>
<field name="hair">brown</field>
</resource>
<resource classname="Quote">
<field name="name">Michael</field>
<field name="username">Lopez</field>
<field name="age">20</field>
<field name="hair">red</field>
</resource>
<resource classname="Quote">
<field name="name">Frank</field>
<field name="username">Lopez</field>
<field name="age">25</field>
<field name="hair">black</field>
</resource>
</resources>
</list>
using this code:
using System.Xml;
using.System.Xml.Linq;
XmlReader reader = XmlReader.Create("http://www.studiovincent.net/list.xml");
XElement el = XElement.Load(reader);
reader.Close();
var items = el.Elements("resources").Elements("resource").Descendants().DescendantNodes();
var items = from item in el.Elements("resources").Elements("resource").Descendants()
where item.Attribute("name").Value == "name" select item.FirstNode;
foreach (XNode node in items)
{
Console.WriteLine(node.ToString());
}
I have this OUTPUT:
Vincent
John
Michael
Frank
Code working very good, but I need get value 31 which corresponds field name="age" where field name="name" is Vincent. How Can I get this result?

I recommend you do as you would when reading XML naturally.
In your code, try to find all the fields with the name attribute set to "name".
This process cannot be used to associate a name with an age. It is more natural to read the XML and check all resource elements. Then add to this element some information described in the field elements.
// Using LINQ to SQL
XDocument document = XDocument.Load("http://www.studiovincent.net/list.xml"); // Loads the XML document.
XElement resourcesElement = document.Root.Element("resources"); // Gets the "resources" element that is in the root "list" of the document.
XElement resourceElementVincent = (from resourceElement in resourcesElement.Elements("resource")// Gets all the "resource" elements in the "resources" element
let fieldNameElement = resourceElement.Elements("field").Single(fieldElement => fieldElement.Attribute("name").Value == "name") // Gets the field that contains the name (there one and only one "name" field in the "resource" element -> use of Single())
where fieldNameElement.Value == "Vincent" // To get only resources called "Vincent"
select resourceElement).Single(); // We suppose there is one and only 1 resource called "Vincent" -> Use of Single()
XElement fieldAgeElement = resourceElementVincent.Elements("field").Single(fieldElement => fieldElement.Attribute("name").Value == "age"); // Gets the corresponding "age" field
int age = int.Parse(fieldAgeElement.Value, CultureInfo.InvariantCulture); // Gets the age by Parse it as an integer
Console.WriteLine(age);
Does it do what you want?

Consider this below XML is there as one of the SQL table's column.
<Root>
<Name>Dinesh</Name>
<Id>2</Id>
</Root>
The objective of the query is to fetch the Name from the XML. In this example we will fetch the 'Dinesh' as the value.
var Query = (from t in dbContext.Employee.AsEnumerable()
where t.active == true
select new Employee
{
Id = t.AtpEventId,
Name = XDocument.Parse(t.Content).Descendants("Root").Descendants("Name").ToList().
Select(node => node.Value.ToString()).FirstOrDefault()
});
Note the following:
t.active == true is just an example to make some condition if needed.
Please note, in the above LINQ query, always use the AsEnumerable, as I did in the first line.
Descendants("Root").Descendants("Name") - here "Root" should be the element matching with the XML, and under Root we have Name element.

Select XML node value by attribute value with multiple levels

I'm looking to get to value further in the XML code than I've seen examples for and with more attributes to consider.
The XML code is:
<?xml version="1.0"?>
<mysqldump xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<database name="Members">
<table_structure name="Logins">
<field Field="ID" Type="int(100)" Null="NO" Key="PRI" Extra="auto_increment" Comment="" />
<field Field="Username" Type="text" Null="YES" Key="" Extra="" Comment="" />
<field Field="Password" Type="text" Null="YES" Key="" Extra="" Comment="" />
<key Table="Logins" Non_unique="0" Key_name="PRIMARY" Seq_in_index="1" Column_name="ID" Collation="A" Cardinality="1" Null="" Index_type="BTREE" Comment="" />
<options Name="Logins" Engine="MyISAM" Version="10" Row_format="Dynamic" Rows="1" Avg_row_length="20" Data_length="40" Max_data_length="281474976710655" Index_length="2048" Data_free="20" Auto_increment="3" Create_time="2011-10-14 19:30:57" Update_time="2011-10-14 19:32:21" Collation="latin1_swedish_ci" Create_options="" Comment="" />
</table_structure>
<table_data name="Logins">
<row>
<field name="ID">1</field>
<field name="Username">MyName</field>
<field name="Password">MyPassowrd</field>
</row>
<row>
<field name="ID">2</field>
<field name="Username">MyName2</field>
<field name="Password">MyPassowrd2</field>
</row>
</table_data>
</database>
</mysqldump>
I'm trying to get to 1, MyName and Password to then enter them into an SQL database.
The issue I'm having is getting through the multiple levels:
<database name="Members">
<table_data name="Logins">
<row>
<field name="ID">
With all the examples I'm finding only ones showing 1 or 2 levels.
This seems to work,
XElement xe = XElement.Load("C:\\PATH.xml");
int count = xe.Descendants("row").Count();
var items = xe.Descendants("field").Where(n => (string)n.Attribute("name") == "ID").ToList();
var items2 = xe.Descendants("field").Where(n => (string)n.Attribute("name") == "Username").ToList();
var items3 = xe.Descendants("field").Where(n => (string)n.Attribute("name") == "Password").ToList();
for (int i = 0; i < count; i++)
{
string res = items[i].Value.ToString();
string res2 = items2[i].Value.ToString();
string res3 = items3[i].Value.ToString();
}
I've got an ID, but I now need all its other elements in its row.
That is,
if (id = 2)
{
string name = username.value;
string password = password.value;
}
where name will result in myName2 and password will be MyPassword2.
I don't want to put usernames and passwords in a list.
Any advice again?

Try with LINQ to XML.
Here you have a tutorial.