Regular Expressions
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What is a regular expression?

A regular expression is a search-pattern, a formula to locate phrases inside text.

An everyday example of something very similar to a regular expression is the the file wildcard character *, where e.g. *.txt would locate text-files.

In case you want to learn more on regular expressions, which are supported by TreePad Business Edition, please see the right-hand column of this page. There you will find a number of links to useful regular expression tutorials and reference sites.



Remember that regular expressions are case sensitive by default! To make a regular expression case-insensitive, insert the four characters (?i) at the start.

Regular expression tutorials and reference:


Regular expression exercising software:
RegexPal (online)
RegExr (online)
Regex-coach (Win, MAC, Linux)
Regulator (Win)


Regular expression books:
Introducing Regular Expressions.
An excellent introductory book on regular expressions (O'Reilly Press).
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