Tests and Conditions

Functions

XPath and XSLT define many functions. Most of these functions take an XPath for a parameter. However, when called with no parameter, they apply to the current node:

 position("//Product")    position() 

The following are the most useful functions:

• position() ”Returns the position of the expression evaluation context.

• last() ”Returns the position of the last node from the expression evaluation context.

• count() ”Returns the number of nodes from the expression evaluation context.

• string() ”Converts its parameter to a string.

• substring() ”Returns a substring of the first argument.

• not() ”Performs a logical not.

• format-number() ”Converts its first argument to a string using a format pattern.

• generate-id () ”Returns a string that uniquely identifies the current node. If the function is called again on the same node, it will return the same ID.