A regular expression is a sequence of characters forming a search pattern for matching text.
TextCrawler 3 implements .NET regular expressions. It can be changed to support VBScript/JavaScript ECMA-262 regular expressions from the Options - Regular Expressions window.
For examples and more advanced commands see this web page:
The match must occur at the end of the string or before \n at the end of the string.
\z
The match must occur at the end of the string
\G
The match must occur at the point where the previous match ended.
Literals (for matching special characters)
Alphanumeric
Matches alphabetical and numerical characters literally.
\n
Matches a new line
\f
Matches a form feed
\r
Matches carriage return
\t
Matches horizontal tab
\v
Matches vertical tab
\a
Matches the bell character
\?
Matches ?
\e
Matches an escape
\*
Matches *
\+
Matches +
\.
Matches .
\|
Matches |
\{
Matches {
\}
Matches }
\\
Matches \
\[
Matches [
\]
Matches ]
\(
Matches (
\)
Matches )
\xxx
Matches the ASCII character expressed by the octal number xxx.
\xdd
Matches the ASCII character expressed by the hex number dd.
\uxxxx
Matches the ASCII character expressed by the UNICODE xxxx.
Character Classes
[xyz]
Match any one character enclosed in the character set.
[^xyz]
Match any one character not enclosed in the character set.
[first-last]
Range - matches any character in range first-last.
.
Match any character except \n.
\w
Match any word character. Equivalent to [a-zA-Z_0-9].
\W
Match any non-word character. Equivalent to [^a-zA-Z_0-9].
\d
Match any decimal digit. Equivalent to [0-9].
\D
Match any non-decimal digit. Equivalent to [^0-9].
\s
Match any whitespace character. Equivalent to [ \t\r\n\v\f].
\S
Match any non-whitespace character. Equivalent to [^ \t\r\n\v\f].
Repetition and Grouping
{x}
Match exactly x occurrences of a regular expression.
{x,}
Match x or more occurrences of a regular expression.
{x,y}
Matches x to y number of occurrences of a regular expression.
?
Match zero or one occurrences. Equivalent to {0,1}.
*
Match zero or more occurrences. Equivalent to {0,}.
+
Match one or more occurrences. Equivalent to {1,}.
Alternation & Grouping
()
Grouping a clause to create a clause. May be nested. "(ab)?(c)" matches "abc" or "c".
|
Alternation combines clauses into one regular expression and then matches any of the individual clauses. "(ab)|(cd)|(ef)" matches "ab" or "cd" or "ef".
$1 - $9 (In replace expression)
Reference a group.
Backreferences
()\n
Matches a clause as numbered by the left parenthesis
