We have a method that writes XML into an XmlWriter, we use this to generate a stream of XML directly without having to go via some form of DOM. However there are occasions where we do want to create a DOM. One approach would be to always build a DOM and to stream from that (to cover both requirements), but we like the performance of writing XML directly. Therefore we want to build a DOM from an XmlWriter.
See How to create a XmlDocument using XmlWriter in .NET? for an example of how to create an XmlDocument from an XmlWriter, albeit using a slightly off-piste code pattern. Are there similar options if I want an XDocument (or XElement subtree) instead?
Have a look at the XContainer.CreateWriter Method:
XContainer.CreateWriter Method
Creates an XmlWriter that can be used to add nodes to the XContainer.
Both XDocument and XElement are XContainers.
Example:
XDocument doc = new XDocument();
using (XmlWriter writer = doc.CreateWriter())
{
// Do this directly
writer.WriteStartDocument();
writer.WriteStartElement("root");
writer.WriteElementString("foo", "bar");
writer.WriteEndElement();
writer.WriteEndDocument();
// or anything else you want to with writer, like calling functions etc.
}
Related
I'm fairly new to XML and very new to using the XMLWriter object. I've been successful in using it to write a "Well Formed" XML file, but after many failed attempts to create the needed header, below, I've decided to come here for some insight.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE IDMS-XML SYSTEM "http://eclipseinc.com/dtd/IDMS-XML.dtd">
<IDMS-XML>
....
Here's the beginning of my code (very standard):
using (XmlWriter xmlWriter = XmlWriter.Create("SendXML.xml"))
{
xmlWriter.WriteStartDocument();
....
I've tried using things like xmlWriter.WriteString() to force it in, but that has been unsuccessful for me. Thanks for any and all insight.
You need to be more clear what the “it” you are trying to “force in” is. Do you mean the <!DOCTYPE ...? That is a doctype declaration, and XmlWriter has a built-in method for adding one. To create a SYSTEM doctype try:
xmlWriter.WriteDocType("IDMS-XML", null, "http://eclipseinc.com/dtd/IDMS-XML.dtd", null);
If that is not what you mean you must be more explicit.
In order to write to the xml file you need to create the XmlTextWriter then create a node to make a header. Hope this helps you out a bit.
XmlTextWriter writer = new XmlTextWriter("filename",System.Text.Encoding.UTF8); writer.WriteStartDocument(True)
writer.WriteStartElement("Start Element Name")
createNode("NodeName", writer)
writer.WriteEndElement()
writer.WriteEndDocument()
writer.Close()
public void createnode(String nodename, XmlTextWriter writer)
{
writer.WriteStartElement("Name Here")
writer.WriteString(nodename)
writer.WriteEndElement()
}
I've got an XDocument created via XDocument's static Load method (taking an XmlReader) as follows:
XDocument doc;
doc = XDocument.Load(reader);
Now, it's necessary at some point to reload the document (restoring to the original version after changes have been made). The obvious way to do this seems to be doc = XDocument.Load(reader);. However, this will create a new XDocument, and any existing references to doc will still point at the old (altered) version despite the fact that we've (re)loaded the original.
Is there a way to load an XmlReader (or even a string or byte[] representation of XML) into an existing XDocument, overwriting the contents? Or would I have to make all of the changes (dropping its elements and adding new ones) manually?
You should be able to do
doc.Root.ReplaceWith( XElement.Load(fileName));
If you want to preserve processing instructions you may need to Load into a temp XDocument first.
You can replace the root of the XDocument.
var oldDoc = new XDocument();
oldDoc.Add(new XElement("OldRoot"));
var newDoc = new XDocument();
newDoc.Add(new XElement("NewRoot"));
oldDoc.Root.ReplaceWith(newDoc.Root);
I am using C# 2.0 and I have got below code:
XmlDocument doc = new XmlDocument();
doc.LoadXml(GetListOfPagesInStructureGroup(m_Page.Id));
In above I am loading my XMLDocument with method which returns as string, now after some processing on above xmldocument I want to apply XSLT on the above XMLDocument to render my desired result according to XSLT and finally my function will return whole rendered XML as string
Please suggest!!
Please suggest on below solution:
XslCompiledTransform xslTransform = new XslCompiledTransform();
StringWriter writer = new StringWriter();
xslTransform.Load("xslt/RenderDestinationTabXML.xslt");
xslTransform.Transform(doc.CreateNavigator(),null, writer);
return writer.ToString();
Thanks!!
Try the XslCompiledTransform class.
There are lots of examples on the web of transforming an XML file to a different format using an XSLT file, like the following:
XslTransform myXslTransform = new XslTransform();
XsltSettings myXsltSettings = new XsltSettings();
myXsltSettings.EnableDocumentFunction = true;
myXslTransform.Load("transform.xsl");
myXslTransform.Transform("input.xml", "output.xml");
However this is only a partial answer, I would like to be able to get the XML input data from a web form and use that as the input data instead of an '.xml' file, but have not found any concrete examples, also using Visual Studio I can see the different constructors and methods that are available and I am not seeing one that accepts xml data in a string format, so it would be very helpful if someone could provide an example of that.
Re " I want my same XMlDocument updated " - it doesn't work like that; the output is separate to the input. If that is important, just use a StringWriter or MemoryStream as the destination, then reload the XmlDocument from the generated output.
Consider in particular: the output from an xslt transformation does not have to be xml, and also: the xslt is most likely using the node tree during the operation; changing the structure in-place would make that very hard.
All,
I have a list of objects which I have serialized to an XML document using XmlSerializer.
However I would like to wrap the whole result into two tags:
<message>
<!-My Serialized content goes here-->
</message>
Do I need to open it as an XML Document and Add a new root element or is there another way of doing it ?
Rgds,
MK
XmlSerializer writes to an XmlWriter. Write the start tag to the writer first, then serialize, and close your message tag at the end.
Example:
XmlWriter writer = // Your writer
XmlSerializer ser = new XmlSerializer(typeof(DateTime));
writer.WriteStartElement("message");
ser.Serialize(writer,DateTime.Now);
writer.WriteEndElement();
The function "WriteStartElement" does not return anything. I find this a little bizzare.
So up until now I have been doing it like this.
XmlDocument xmlDoc = new XmlDocument();
XmlTextWriter xmlWriter = new XmlTextWriter(m_targetFilePath, System.Text.Encoding.UTF8);
xmlWriter.Formatting = Formatting.Indented;
xmlWriter.WriteProcessingInstruction("xml", "version='1.0' encoding='UTF-8'");
xmlWriter.WriteStartElement("client");
xmlWriter.Close();
xmlDoc.Load(m_targetFilePath);
XmlElement root = xmlDoc.DocumentElement;
Saving the doc, then reloading it to get hold of the start element so i can write attributes to it. Does anybody know the correct way of doing this because I'm pretty sure what I'm doing isn't right.
I tried to use xmlWriter.AppendChild() but it doesnt seem to write out anything. :(
If you are using 3.5 or higher, XDocument would make you fall in love.
Have you tried something like this ?
// add the root node
xmlWriter.WriteStartElement("client");
// add the attribute to root node
xmlWriter.WriteStartAttribute("foo");
// add the value of the attribute
xmlWriter.WriteValue("attribute value...");
// close the attribute to root node
xmlWriter.WriteEndAttribute();
// close the root node
xmlWriter.WriteEndElement();
Have you looked at using XmlSerializer? Create a class to hold all your data, create an instance of your class and then use XmlSerializer to write it out to an XML file.