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Regular Expression Language Elements 

The .NET Framework SDK provides an extensive set of regular expression tools that enable you to efficiently create, compare, and modify strings as well as rapidly parse large amounts of text and data to search for, remove, and replace text patterns.

This section details the set of characters, operators, and constructs that you can use to define regular expressions.

In This Section

Character Escapes

Provides information on the set of escape characters that signal to the regular expression parser that the character is not an operator and should be interpreted as a matching character.


Provides information on the special constructs used in replacement patterns.

Character Classes

Provides information on the set of regular expression characters that define the substring to match.

Regular Expression Options

Provides information on the set of options that modify a regular expression pattern's matching behavior.

Atomic Zero-Width Assertions

Provides information on zero-width assertions that cause a match to succeed or fail depending on the regular expression parser's current position in the input string.


Provides information on optional quantity data that modify a regular expression.

Grouping Constructs

Provides information on grouping constructs that cause a regular expression to capture groups of subexpressions.

Backreference Constructs

Provides information on regular expression backreference modifiers.

Alternation Constructs

Provides information on alternation information that modifies a regular expression to allow either/or matching.

Miscellaneous Constructs

Provides information on miscellaneous constructs that modify regular expression matching behavior.


System.Text.RegularExpressions Namespace

Provides class library reference information for the .NET Framework System.Text.RegularExpressions namespace.

Related Sections

.NET Framework Regular Expressions

Provides a brief introduction to .NET regular expressions.

Regular Expressions as a Language

Provides an overview of the programming language aspect of regular expressions.

Regular Expression Classes

Provides detailed information and code examples illustrating how to use the regular expression classes.

Details of Regular Expression Behavior

Provides detailed information about the capabilities and behavior of .NET Framework regular expressions.

Regular Expression Examples

Provides code examples illustrating typical uses of regular expressions.