namespace-uri

The namespace-uri function returns a string representing the namespace URI of the first node in a given node-set.

Syntax

namespace-uri( [node-set] )

node-set (optional): The namespace URI of the first node in this node-set will be returned. If this argument is omitted, the current context node will be used.

A string representing URI of the namespace in which the given node resides.

If the given node does not have a specified namespace, the returned string will be an empty string.
For nodes other than element and attribute nodes, the returned string will always be an empty string.

Supported.