new()¶

This constructor follows the often seen named parameter method call. Parameters you can use are: filename, parser, xml, ioref and context. The filename parameter specifies an XML file to parse. The xml parameter specifies a string to parse, and the ioref parameter specifies an ioref to parse. The context option allows you to specify a context node. The context node has to be in the format of a node as specified in XML::XPath::XMLParser. The 4 parameters filename, xml, ioref and context are mutually exclusive - you should only specify one (if you specify anything other than context, the context node is the root of your document). The parser option allows you to pass in an already prepared XML::Parser object, to save you having to create more than one in your application (if, for example, you are doing more than just XPath).

    my $xp = XML::XPath->new( context => $node );

It is very much recommended that you use only 1 XPath object throughout the life of your application. This is because the object (and it's sub-objects) maintain certain bits of state information that will be useful (such as XPath variables) to later calls to find(). It's also a good idea because you'll use less memory this way.

find($path, [$context])¶

The find function takes an XPath expression (a string) and returns either an XML::XPath::NodeSet object containing the nodes it found (or empty if no nodes matched the path), or one of XML::XPath::Literal (a string), XML::XPath::Number or XML::XPath::Boolean. It should always return something - and you can use ->isa() to find out what it returned. If you need to check how many nodes it found you should check $nodeset->size. See XML::XPath::NodeSet. An optional second parameter of a context node allows you to use this method repeatedly, for example XSLT needs to do this.

findnodes($path, [$context])¶

Returns a list of nodes found by $path, optionally in context $context. In scalar context returns an XML::XPath::NodeSet object.

matches($node, $path, [$context])¶

Returns true if the node matches the path (optionally in context $context).

findnodes_as_string($path, [$context])¶

Returns the nodes found reproduced as XML.The result isn't guaranteed to be valid XML though.

findvalue($path, [$context])¶

Returns either a "XML::XPath::Literal", a "XML::XPath::Boolean" or a "XML::XPath::Number" object.If the path returns a NodeSet,$nodeset->to_literal is called automatically for you (and thus a "XML::XPath::Literal" is returned).Note that for each of the objects stringification is overloaded, so you can just print the value found, or manipulate it in the ways you would a normal perl value (e.g. using regular expressions).

exists($path, [$context])¶

Returns true if the given path exists.

getNodeText($path)¶

Returns the XML::XPath::Literal for a particular XML node. Returns a string if exists or '' (empty string) if the node doesn't exist.

setNodeText($path, $text)¶

Sets the text string for a particular XML node. The node can be an element or an attribute. If the node to be set is an attribute, and the attribute node does not exist, it will be created automatically.

createNode($path)¶

Creates the node matching the $path given. If part of the path given or all of the path do not exist, the necessary nodes will be created automatically.

set_namespace($prefix, $uri)¶

Sets the namespace prefix mapping to the uri.

Normally in "XML::XPath" the prefixes in XPath node test take their context from the current node. This means that foo:bar will always match an element <foo:bar> regardless of the namespace that the prefix foo is mapped to (which might even change within the document, resulting in unexpected results). In order to make prefixes in XPath node tests actually map to a real URI, you need to enable that via a call to the set_namespace method of your "XML::XPath" object.

clear_namespaces()¶

Clears all previously set namespace mappings.

$XML::XPath::Namespaces¶

Set this to 0 if you don't want namespace processing to occur. This will make everything a little (tiny) bit faster, but you'll suffer for it, probably.