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
Processing...

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^@([^\s]+).+global\s+([^\s]+)\s+([^,]+).+"; string input = @"; ModuleID = 'foo.c' source_filename = ""foo.c"" target datalayout = ""e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"" target triple = ""x86_64-pc-linux-gnu"" @Test = dso_local global i32 5, align 4 ; Function Attrs: noinline nounwind optnone uwtable define dso_local void @main() #0 { ret void } attributes #0 = { noinline nounwind optnone uwtable ""correctly-rounded-divide-sqrt-fp-math""=""false"" ""disable-tail-calls""=""false"" ""frame-pointer""=""all"" ""less-precise-fpmad""=""false"" ""min-legal-vector-width""=""0"" ""no-infs-fp-math""=""false"" ""no-jump-tables""=""false"" ""no-nans-fp-math""=""false"" ""no-signed-zeros-fp-math""=""false"" ""no-trapping-math""=""false"" ""stack-protector-buffer-size""=""8"" ""target-cpu""=""x86-64"" ""target-features""=""+cx8,+fxsr,+mmx,+sse,+sse2,+x87"" ""unsafe-fp-math""=""false"" ""use-soft-float""=""false"" } !llvm.module.flags = !{!0} !llvm.ident = !{!1} !0 = !{i32 1, !""wchar_size"", i32 4} !1 = !{!""clang version 10.0.0-4ubuntu1 ""} "; RegexOptions options = RegexOptions.Multiline; 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