key( )
node-set
key(string keyName, string value
)node-set
key(string keyName, node-set values
)
The key( )
function
returns a node-set containing all nodes in the source document
that have a key with the name given by the first argument and the
value given by the second argument. If the second argument is a
node-set, then the node-set returned contains all nodes that have
a key with the specified name and a value that matches that of any
node in the second argument. Otherwise, the returned node-set
contains all nodes that have a key with the specified name and a
value that matches the second argument's string-value. Key names
and values are assigned to nodes using the xsl:key
element.