How can I add xml attributes with different prefixes/namespaces in C#?

Question

I need to be able to create an XML Document that looks like this:

 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <rootprefix:rootname 
     noPrefix="attribute with no prefix"
     firstprefix:attrOne="first atrribute"
     secondprefix:attrTwo="second atrribute with different prefix">

     ...other elements...

 </rootprefix:rootname>

Here's my code:

XmlDocument doc = new XmlDocument();

XmlDeclaration declaration = doc.CreateXmlDeclaration("1.0", "UTF-8", "yes");
doc.AppendChild(declaration);

XmlElement root = doc.CreateElement("rootprefix:rootname", nameSpaceURL);
root.SetAttribute("schemaVersion", "1.0");

root.SetAttribute("firstprefix:attrOne", "first attribute");
root.SetAttribute("secondprefix:attrTwo", "second attribute with different prefix");

doc.AppendChild(root);

Unfortunately, what I'm getting for the second attribute with the second prefix is no prefix at all. It's just "attrTwo"--like the schemaVersion attribute.

So, is there a way to have different prefixes for attributes in the root element in C#?

Lemal

Answer 1

This is just a guide for you. May be you can do:

        NameTable nt = new NameTable();
        nt.Add("key");

        XmlNamespaceManager ns = new XmlNamespaceManager(nt);
        ns.AddNamespace("firstprefix", "fp");
        ns.AddNamespace("secondprefix", "sp");

        root.SetAttribute("attrOne", ns.LookupPrefix("fp"), "first attribute");

        root.SetAttribute("attrTwo", ns.LookupPrefix("sp"), "second attribute with different prefix");

This will result in:

        <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
        <rootprefix:rootname schemaVersion="1.0" d1p1:attrOne="first attribute" d1p2:attrTwo="second attribute with different prefix" xmlns:d1p2="secondprefix" xmlns:d1p1="firstprefix" xmlns:rootprefix="ns" />

Hope this will be of any help!

Gunman

worth noting that the NameTable and AddNameSpace is needed only if you need to determine the shorthand of the namespace rather then the default naming convention (d1p1, d1p2, ...) – Zephan

Answer 2

I saw a post on another question that ended up solving the issue. I basically just created a string that had all the xml in it, then used the LoadXml method on an instance of XmlDocument.

string rootNodeXmlString = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>"    
    + "<rootprefix:rootname schemaVersion=\"1.0\" d1p1:attrOne=\"first attribute\"" 
    + "d1p2:attrTwo=\"second attribute with different prefix\" xmlns:d1p2=\"secondprefix\""
    + "xmlns:d1p1=\"firstprefix\" xmlns:rootprefix=\"ns\" />";
doc.LoadXml(rootNodeXmlString);

Lemal

This is the fastest solution. Thanks for this. I did this too, and I replaced InnerXml later with the desired XML. I think it's extremely hard to customize the output just the way you want it with standard APIs. You have no control in what order attributes are written. – Funicle