The prefix of the node, or the empty string if the node has no prefix.
Setting this property, when permitted, changes the XmlNode.Name property, which holds the qualified name, on Element and Attribute nodes. Setting this property on node types that cannot have a prefix (such as Text, Comment, EntityReference, CDATA, ProcessingInstruction, Document, and DocumentFragment) has no effect. Changing the prefix of an attribute that is known to have a default value, does not make a new attribute with the default value and the original prefix appear, since the namespace URI and local name do not change.