An XPath expression returns either a node-set, a string,
a Boolean, or a number.
The following operators are available for use with XPath expressions:
- Addition operator
- Format: +
- Adds two numbers.
- You can also use it to add two expressions that return a numeric
result.
- Minus operator
- Format: -
- Yields the difference between two numbers.
- The minus (-) operator can also indicate the negative value of
a numeric expression.
- Multiply operator
- Format: *
- Multiplies two numbers.
- Division Operator
- Format: div
- Divides two numbers and returns a floating decimal.
- Mod Operator
- Format: mod
- Divides two numbers and returns only the remainder.
- Equal Operator
- Format: =
- If the expression is equal to the specified value, the operator
returns true. If the expression is not equal to the specified value,
the operator returns false.
- Example:
price=7.80
- Returns: True, if price is 7.80; false, if price is 7.90
- Not equal to Operator
- Format: !=
- If the expression is not equal to the specified value, the operator
returns true. If the expression is equal to the specified value, the
operator returns false.
- Example:
price!=7.80
- Returns: True if price is 7.90; false if price is 7.80
- Less than Operator
- Format: <
- Compares two numeric expressions and determines whether expression1 is
less than expression2; if so, the operator returns
true. If expression1 is greater than or equal to expression2,
the operator returns false.
- Example:
price<7.80
- Returns: True if price is 7.00; false if price is 7.80
- Less than or equal to Operator
- Format: <=
- Compares two specified numeric expressions and determines whether expression1 is
less than or equal to the expression2; if it is,
the operator returns true. If the expression1 is
greater than expression2, the operator returns
false.
- Example:
price<=7.80
- Returns: True if price is 7.00; false if price is 7.90
- Greater than Operator
- Format: >
- Compares two numeric expressions and determines whether expression1 is
greater than expression2; if it is, the operator
returns true. If expression1 is less than or equal
to expression2, the operator returns false.
- Example:
price>7.80
- Returns: True if price is 7.90; false if price is 7.80
- Greater than or equal to Operator
- Format: >=
- Compares two numeric expressions and determines whether expression1 is
greater than or equal to expression2 (true) or expression1 is
less than expression2 (false).
- Or Operator
- Format: or
- Logical or.
- And Operator
- Format: and
- Logical and.
- Parentheses operator
- Format: ( )
- Controls the order in which the operators execute in the expression.
Parentheses override the normal precedence order and cause the expressions
within the parentheses to be evaluated first. When parentheses are
nested, the contents of the innermost parentheses are evaluated before
the contents of the outer ones.
- Boolean operator
- Format: [ ]
- A filter is evaluated as a Boolean on every node that is within
the current context. If the Boolean evaluates to true, the node is
included in the returned set; otherwise, it is excluded. Filters are
enclosed in brackets.
- Root operator
- Format: /
- Selects from the root node.
- Anywhere operator
- Format: //
- Selects nodes in the document that match the selection no matter
where they are.
- Attribute operator
- Format: @
- Identifies an attribute of a node.