How to create XmlElement attributes with prefix?

Question

I need to be able to define an attribute with a prefix in a xml element.

For instance...

Answer 1

If you've already declared your namespace in the root node, you just need to change the SetAttribute call to use the unprefixed attribute name. So if your root node defines a namespace like this:

<People xmlns:s='http://niem.gov/niem/structures/2.0'>

You can do this and the attribute will pick up the prefix you've already established:

// no prefix on the first argument - it will be rendered as
// s:id='ID_Person_01'
TempElement.SetAttribute("id", "http://niem.gov/niem/structures/2.0", "ID_Person_01");

If you have not yet declared the namespace (and its prefix), the three-string XmlDocument.CreateAttribute overload will do it for you:

// Adds the declaration to your root node
var attribute = xmlDocToRef.CreateAttribute("s", "id", "http://niem.gov/niem/structures/2.0");
attribute.InnerText = "ID_Person_01"
TempElement.SetAttributeNode(attribute);

Answer 2

Try creating the attribute directly and adding it to the element:

XmlAttribute attr = XmlDocToRef.CreateAttribute("s", "id", "http://niem.gov/niem/structures/2.0");
attr.InnerText = "ID_Person_01";
TempElement.Attributes.Append(attr);

Answer 3

Since my search kept taking me here, I'll answer this for XElement. I don't know if this solution is also valid for XmlElement, but it will hopefully at least help others using XElement, who end up here.

Based on this I added xml:space="preserve" to all data-nodes in some template, before looking up and adding their contents. It's weird code IMO (I would prefer three parameters as shown above, but it does the job:

 foreach (XElement lElement in root.Descendants(myTag))
 {
      lElement.Add(new XAttribute(root.GetNamespaceOfPrefix("xml") + "space", "preserve"));
 }

Answer 4

The XMLDocument.CreateAttribute method can take 3 strings: specified Prefix, LocalName, and NamespaceURI. You could then add the attribute to the element. Something like this might work for you:

XmlAttribute newAttribute = XmlDocToRef.CreateAttribute("s", "id", "http://niem.gov/niem/structures/2.0");
TempElement.Attributes.Append(newAttribute):