Whether XML element attribute name can be empty:
<?xml version="1.0" encoding="utf-8"?>
<test>
<tables>
<gg qqq="">
<ss ""=""/>
<mm ""=""/>
</gg>
</tables>
</test>
I am getting an exception I cant to load this. Is this possible?
No, this will produce invalid XML. Attribute must have both name and value. How do you image opposite?
No this can not be done.
XML has empty element concept[If you are trying to implement that].
In that whole element is kept empty and said to be null as follow>>
<abc></abc>
<DefaultTaxPrice></DefaultTaxPrice>
Short answer, no. If you want to add value but not know what is the name of the value in XML, insert in into the body instead.
<ss>value</ss>
This way, your ss will be treated as a value
Related
I have an XML file, that looks like this (only a snippet)
<?xml version="1.0" encoding="UTF-8" ?>
<Message>
<Header>
<Message_Type>RFP</Message_Type>
<Message_Date>2020-11-05T09:36:03+01:00</Message_Date>
<Sequence_Number>225</Sequence_Number>
etc...
I am looking for the fastest way to find the value RFP.
All i know is the elements name that I need to get a value for.
for example, I get names like Message_Type and Message_Date and now I need to get the value for these element names.
There are no attributes in the xml
I did some searching and all I can find is how to find an element with a specific attribute, or all elements with a specific value, stuff like that.
It seems like something very basic but i just cant see how to do it.
I tried something like this
var headerElements = XElement.Load(fileName).Elements("Header");
var element = headerElements.Where(x => x.Element("Message_Type").Name == "Message_Type");
this fills element with the entire Header which seems useless to me. I only need the value of one element in ´Header`, not all
So could some kind soul here put me in the right direction on how to do this ?
Your current query is using a Where call, which will only filter - it doesn't change which elements you're looking at.
What you want is just the Element method itself:
var messageTypeElements = headerElements.Elements("Message_Type");
That will give you all the <Message_Type> elements from all the Header elements.
If in fact you only have a single <Header> and a single <Message_Type> then you can use Element instead:
var message = XElement.Load(fileName);
var header = message.Element("Header");
var messageType = header.Element("Message_Type");
(The Element method will return the first element with the given name, or null if there aren't any. We don't know whether your program should just throw an exception if there are no headers/message_types, or handle it more gracefully.)
Maybe I'm not doing this correctly. But I'm using MusicXML, along with XSD.exe to generate the C# classes against the DTD.
According to the documentation, along with a sample xml file, the <NOTE> element contains an empty <CHORD> element, if the <NOTE> is a part of a <CHORD>. The code generated looks like this:
[System.Xml.Serialization.XmlElementAttribute("chord", typeof(empty))]
When I deserialize the XML into a c# object, it works great, but the <CHORD> seems to disappear. Does .NET just ignore the CHORD element in this sample XML?
<note>
<chord/>
<pitch>
<step>E</step>
<alter>-1</alter>
<octave>4</octave>
</pitch>
<duration>1</duration>
</note>
Thanks!
Do you mean the chord element dissapears when you serialize to XML, as null elements don't serialize by default
If you want to render it as an empty element like
<chord />
you can set use the isnullable property
XML Serialization and null value - C#
As linked in another question you might want to have a look at this article about the representation of null in XML Schema files:
http://www.ibm.com/developerworks/xml/library/ws-tip-null/index.html
I am trying to use XDocument.Parse(string s) to parse some XML that is being returned from a REST based API. After the XML is parsed, it creates a new XDocument, but the document doesn't contain the properly parsed XML nodes. The name of the first node is the correct node name, but the value is the the concatenation of all the text from the XML, regardless of which Element is belongs to. Can anybody help me figure out what is going on?
XML
<sci_reply version="1.0">
<send_message>
<device id="00000000-00000000-00000000-00000000">
<error id="303">
<desc>Invalid target. Device not found.</desc>
</error>
</device>
<error>Invalid SCI request. No valid targets found.</error>
</send_message>
</sci_reply>
Debug View of XDocument Object
That's the expected behavior. The Value of a an XML element is concatenation of values of all its children. If you want to actually access the XML, read something about LINQ to XML or classes in the System.Xml.Linq namespace.
Thats just the debugger being nice.
The root is being displayed with all of its children.
If I get the path to a specific node as a string can I somehow easily find said node by using Linq/Method of the XElement ( or XDocument ).
There are so many different types of XML objects it would also be nice if as a added bonus you could point me to a guide on why/how to use different types.
EDIT: Ok after being pointed towards XPathSelectElement I'm trying it out so I can give him the right answer I can't quite get it to work though. This is the XML I'm trying out
<Product>
<Name>SomeName</Name>
<Type>SomeType</Type>
<Quantity>Alot</Quantity>
</Product>
and my code
string path = "Product/Name";
string name = xml.XPathSelectElement(path).Value;
note my string is coming from elsewhere so I guess it doesn't have to be literal ( at least in debug mode it looks like the one above). I've also tried adding / in front. It gives me a null ref.
Try using the XPathSelectElement extension method of XElement. You can pass the method an XPath expression to evaluate. For example:
XElement myElement = rootElement.XPathSelectElement("//Book[#ISBN='22542']");
Edit:
In reply to your edit, check your XPath expression. If your document only contains that small snippet then /Product/Name will work as the leading slash performs a search from the root of the document:
XElement element = document.XPathSelectElement("/Product/Name");
If there are other products and <Product> is not the root node you'll need to modify the XPath you're using.
You can also use XPathEvaluate
XDocument document = XDocument.Load("temp.xml");
var found = document.XPathEvaluate("/documents/items/item") as IEnumerable<object>;
foreach (var obj in found)
{
Console.Out.WriteLine(obj);
}
Given the following xml:
<?xml version="1.0" encoding="utf-8" ?>
<documents>
<items>
<item name="Jamie"></item>
<item name="John"></item>
</items>
</documents>
This should print the contents from the items node.
I have a xml file that looks like this :
<?xml version="1.0" encoding="utf-8"?>
<config>
<node id="1" />
</config>
Now I try to deserialize it, but always get the error :
<config xmlns=''> was not expected
Anyone how to fix this ? I dont have any control over the xml.
Thanx
Why not just load it in as a DOM (e.g. using XmlDocument or XDocument) and extract the data yourself? Assuming it wasn't saved with XmlSerializer, there's no point in trying to deserialize it that way.
EDIT: It would help if you'd give us some background here. If this isn't a valid XmlSerializer output, what is it? Was it originally a valid file, but something has stripped out the namespaces? If so, what else has it done?
You may well be able to get away with just reapplying the namespace everywhere yourself (to every element) although that may be annoying do. Currently we can't really tell though.