Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression

/
/
gmi

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @" <a id=""(.*?)<\/a>"; string input = @"{% comment %} Use this template to create the Appian_Release_Notes.md page for each new version of Appian. Any changes to this template should be discussed with the Information Development team. {% endcomment %} New features are described below in detail. Behavior changes, resolved issues, deprecations, and removals are called out their own sections. {% comment %} ### <a id=""Example_New_Feature""></a> Example New Feature ### This is a short description of the new feature. Group two or more closely related features using a common section with h4 subsections. Link to associated documentation as shown below (based on the number of links). See also: [Associated Documentation](Associated_Documentation.md) See also: [Associated Documentation](Associated_Documentation.md) and [Associated Documentation](Associated_Documentation.md) See also: [Associated Documentation](Associated_Documentation.md), [Associated Documentation](Associated_Documentation.md), and [Associated Documentation](Associated_Documentation.md) {% endcomment %} ## <a id=""User_Interfaces""></a> User Interfaces ## This section describes new features for user interfaces, including Tempo, sites, and embedded interfaces. ### Sites Revolution ### #### <a id=""Tempo_Reports_in_Sites""></a> Tempo Reports in Sites ### In addition to task reports, actions and record types, designers can now configure sites to have Tempo reports. Making it easier for sites only users to view and analyze data. <img class=""screenshot"" src=""images/release_notes/SitesTempoReports.png""/> [configure sites with reports](Sites.md#Configure_a_Site_Page). #### <a id=""Inline_Task_Management""></a> Inline Task Management ### Task management has improved for users of all Appian user environments. All task management controls for SAIL [tasks](Tasks.md), including save changes, reassign, and reject, have been moved to above the task form. The left-hand navigation bar no longer appears in Tempo when viewing SAIL tasks, allowing task forms to occupy the full page width. These task management controls are now available to [sites](Sites.md) users for the first time. Users of [embedded](Embedded_Interfaces.md) tasks now have the option to save changes to SAIL tasks. <img src=""images/release_notes/InlineTaskControls.png"" class=""screenshot""/> #### <a id=""User_Record_in_Sites""></a> User Record in Sites ### We have made it possible for designers to configure the User record and User record links in sites. <img class=""screenshot"" src=""images/release_notes/SitesUserRecord.png""/> #### <a id=""User_Profile_in_Sites""></a> User Profile in Sites ### Users can now update their profiles in a site by clicking on their avatar in the header and clicking on the Profile button. <img class=""screenshot"" src=""images/release_notes/SitesUserProfile.png""/> #### Wider Sites ### "; RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx