Introduction to Regular Expressions

Explains the concept of regular expressions by comparing with concepts that are already familiar to most readers.

Indicates how regular expressions extend conventional search criteria through practical examples.

Explains the characters that comprise a regular expression, the characters that comprise metacharacters, and the behavior of metacharacters.

Describes the components of a regular expression and the relationship between the components and delimiters.

Explains how regular expressions are evaluated and how the sequence and syntax of the regular expression effects the result.

Distinguishes ordinary characters from metacharacters and illustrates how to combine single-character regular expressions to create larger expressions.

Explains the concept of escaping characters and how to create a regular expression that matches metacharacters.

Lists the escape sequences that are used to represent non-printing characters in a regular expression.

Illustrates how regular expressions use periods, escape characters, and brackets to create sequences that return specific results.

Explains how to create regular expressions when you cannot specify how many characters comprise a match.

Indicates how to fix a regular expression to either the beginning of a line or the end of a line and how to create regular expressions that occur within a word, at the beginning of a word, or at the end of a word.

Illustrates how alternation uses the '|' character to allow a choice between two or more alternatives and how grouping works in conjunction with alternation to further refine the result.

Explains how to create regular expressions that can access part of a stored matched pattern without recreating the regular expression that found the matched pattern.

Clarifies how pattern-matching notation of regular expressions allows developers to quickly parse large amounts of text to find specific character patterns; to extract, edit, replace, or delete text substrings; or to add the extracted strings to a collection in order to generate a report.

Provides a list of links to code examples that illustrate the use of regular expressions in common applications.