Echelon IzoT NodeBuilder User Manual
Page 202

Expression
Description
?
The question mark replaces one or zero characters. The search must
contain at least two other characters. Use \? to represent a question mark
character.
.
The period replaces exactly one character. The search must contain at
least two other characters. Use \. to represent a period character.
(pattern)
Matches the pattern and remembers the match. The matched substring
can be retrieved by using ‘\0’-‘\9’ later in the regular expression, where
‘0’-‘9’ are the number of the pattern.
Example: regular expression (re).*\0s+ion will match regular expression.
First the search matches re string and stores that pattern with index 0. .*
will match gular exp in regular expression. The \0 expression retrieves
the pattern with index 0 (for example, re). This re that matches the re in
expression. Finally the s+ion expression matches ssion.
x|y
Matches either character x or y. You can combine more than two
characters like x|y|z.
{n}
The preceding character must match exactly n times. For example
bo{2}k{2}e{2}per would match bookkeeper. n must be a positive
integer.
{n,}
The preceding character must match n or more times (for example,
bo{2,}k{2,}e{2,}per would find instances of bookkeeper,
boookkeeeeper, and so on. n must be a positive integer.
{n,m}
The preceding character must match between n and m times. n and m
must be positive integers, and m must be greater than n.
[xyz]
Matches any of the enclosed characters. [xyz] produces identical results
to x|y|z.
[^xyz]
Matches any character other than the enclosed characters.
\b
Matches a word boundary.
\B
Matches anything other than a word boundary.
\d
Matches any numerical digit (0-9).
\D
Matches any non digit.
\f
Matches a form feed.
\n
Matches a new line character.
\s
Matches any white space character.
\S
Matches any non-white space character.
\t
Matches any tab character.
\v
Matches any vertical tab character.
\w
Matches any letter, number, or underscore.
\W
Matches anything other than a letter, number or underscore.
\
Where
(pattern), above).
/n/
Where n is any number from 1-255. Matches the character with the
ASCII value n.
188
Developing Device Applications