8.1 XML Navigation Using XPath 179
sum(set) Sum of a set of matching elements or attributes
count(set) Number of matching elements or attributes in a set
position() The position in the current context
last() The last position in the current context
and The logical and operator
or The logical or operator
not The logical negation operator
+ Addition of two values- Subtraction. Because names can have hyphens
always put spaces before and after the minus sign.
div Division
mod The remainder after division
- Multiplication
round(number) Round a number to the nearest integer
floor(number) Round down to an integer
ceiling(number) Round up to an integer
. Navigate to the current element
.. Navigate to the parent element
/ Navigate to a child element
// Navigate to any contained (descendant) element
| Match either of two choices
starts-with(text) Test that text begins in a specified way
substring(start,end,text) A part of some text
string-length(text) The number of characters in some text
= Test for equality
!= Test for not equal to
< Test for less than. Note that<has a meaning
in XML, so one must use the “escaped” notation.
Test for greater than
<= Test for less than or equal to
= Test for greater than or equal to
Table 8.1 Some of the XPath operators