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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

use strict; my $str = 'using System.Linq; using NineYi.ERPV2.DA.AppDB.Tables; namespace NineYi.ERPV2.DA.Repositories.DbRepositories { /// <summary> /// AppDbRepository /// </summary> public class AppDbRepository : IAppDbRepository { /// <summary> /// AppDbContext /// </summary> private AppDbContext _appDbContext; /// <summary> /// Initializes a new instance of the <see cref="AppDbRepository" /> class. /// </summary> /// <param name="appDbContext">AppDbContext</param> public AppDbRepository(AppDbContext appDbContext) { this._appDbContext = appDbContext; } /// <summary> /// SaveChanges /// </summary> public void SaveChanges() { this._appDbContext.SaveChanges(); } /// <summary> /// QueryUserCoupons /// </summary> /// <returns>UserCoupons</returns> public IQueryable<user_coupon> QueryUserCoupons() { return this._appDbContext.user_coupon; } /// <summary> /// QueryPubContents /// </summary> /// <returns>PubContents</returns> public IQueryable<pub_content> QueryPubContents() { return this._appDbContext.pub_content; } } }'; my $regex = qr/public ([\w><]+ [\w><]+\(\))\s+{[^}]+}/mp; my $subst = '\\1;'; my $result = $str =~ s/$regex/$subst/rg; print "The result of the substitution is' $result\n";

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 Perl, please visit: http://perldoc.perl.org/perlre.html