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
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^\w++\W++((?<=\"")[\w-]+(?=""))\W+((?<=\"")[\w-]+(?=""))[\S\s]+?(count\W+=.*)[\S\s]+?^}$"; string input = @"resource ""aws_iam_role"" ""my_test_payer_specific_role"" { count = ""${(var.payer_account == ""380834257621"")?1:0}"" name = ""my_test_payer_specific_role"" max_session_duration = ""7200"" assume_role_policy = ""${data.aws_iam_policy_document.my_test_payer_specific_role-policy.json}"" tags = ""${var.resources_tags}"" lifecycle { ignore_changes = [ ""permissions_boundary"" ] } } resource ""aws_iam_role_policy_attachment"" ""my_test_payer_specific_role-policy-attachment"" { role = ""${aws_iam_role.my_test_payer_specific_role.name}"" count = ""${(var.payer_account == ""380834257621"")?1:0}"" policy_arn = ""arn:${var.partition}:iam::aws:policy/AdministratorAccess"" } data ""aws_iam_policy_document"" ""my_test_payer_specific_role-policy"" { count = ""${(var.payer_account == ""380834257621"")?1:0}"" statement { actions = [""sts:AssumeRole""] principals { type = ""AWS"" identifiers = [""arn:${var.partition}:iam::${var.payer_account}:root"", ""arn:${var.partition}:iam::380834257621:root""] } } }"; 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