Help Returns a Spread of matches to XPath Queries
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about XPath (XML)

Returns a Spread of matches from an XPath-Query.
XPath is a W3C Recommendation and describes a way how to navigate through XML Documents.
We can use XPath to select values of elements from a XML File. Every XPath Expression must start with "/". An XPath expression works like navigating a file system; where a forward slash (/) selects subdirectories.
Inside of [ ] Brackets you can specify you your Query. Then you keep on defining the Path with "/". The "@" means that you select an attribute.

There are a lot of functions and operators you can use. We cant give a complete instruction to XPath. But try the Microsoft Reference Online.
A good site to learn everything about the X-Stuff ishttp://www.w3schools.com
A good reference of XPath Syntax and Fuctions is http://msdn.microsoft.com/en-us/library/ms256115.aspx

Examples

if you ever had a look at a .v4p file using a texteditor you will see that those are also pure XML.
so the following examples will be based on vvvv's own files.

parsing a .v4p file with this query

will output a spread containing all Descriptive Names used in the patch.

will output the nodename of the node with the id ="7"

so this way you can navigate in XML with paths similar to the folderstructures of your harddisk.

you can do more advanced queries like:

which will output a spread containg all id's of IOBox Values which do NOT have a Descriptive Name.

hints

• you can input a spread of queries also
• you can parse the "live"-patch you are running using
• PatchAlias (VVVV)
• PatchAlias (VVVV Name)
• PatchAlias (VVVV ActivePatch)
• GetPatch (VVVV)
• you even can modify a running patch using
• SetPatch (VVVV)

See also XSLT (XML)