Gain insights into pattern matching with regular expressions in C#. Explore data validation, information extraction, and more using String and Regex APIs with practical examples.

Regular expressions provide an extremely powerful method for pattern matching with strings. They are very useful for parsing information like dates, phone numbers, or zip codes from important text files, such as code files, log files, spreadsheets, or documents. The course discusses everyday use cases of regular expressions, e.g., data validation, information extraction, pattern matching, and search and replace.

This course will teach you the core concepts of pattern matching, character classes, special and meta characters, and quantifiers. You will also learn conditional regular expressions including lookahead and lookbehind assertions. You will also learn the APIs used in C# for regular expressions with hands-on code widgets. 

This course will teach you how to perform pattern matching with a regular expression using String and Regex APIs for the above-mentioned practical use cases in C#.

Tarun Telang

Tarun Telang is a passionate software engineer, leader, architect, author, and active contributor in various online technical forums.

C# and Microsoft Expert

Working with Regular Expressions in C#

The `Group` class is a part of the `System.Text.RegularExpressions` namespace. It represents a matched subexpression within a regular expression pattern. Each group has a number starting at 1.

The `Groups` property returns a list of `Group` objects. To retrieve the value of a capture group, we use the `Value` property of the `Group` object.

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We can also use captured sub-strings in the replacement string of a `Replace()` method. To do this, we use the `$n` notation where `n` is the index of the captured group.

The following code shows how to use captured sub-strings in a replacement string:

Learn how to work with capture groups, including retrieving captured sub-strings and using them in the matched output.

Introduction

Building Blocks of .NET Regular Expressions

Advanced Concepts

Course Wrap Up

Working with Capture Groups

The `Group` class

Working with Capture Groups

The Group class

The `Group` class