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...

<nc:Person s:id="ID_Person_01"></nc:Person>

In order to do this I though that the following would have worked.

XmlElement TempElement = XmlDocToRef.CreateElement("nc:Person", "http://niem.gov/niem/niem-core/2.0");
TempElement.SetAttribute("s:id", "http://niem.gov/niem/structures/2.0", "ID_Person_01");

Unfortunately, XmlElement.SetAttribute(string, string, string) does not seem to support parsing the prefix as I receive the error below.

The ':' character, hexadecimal value 0x3A, cannot be included in a name.

How would I define an attribute with prefix?

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'&gt;

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
XmlAttribute 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

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):