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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @",(?=\{""TimePeriod"":)"; string input = @"{""TimePeriod"": {""Start"": ""2017-03-01"", ""End"": ""2017-04-01""}, ""Total"": {""UnblendedCost"": {""Amount"": ""2942.25119998"", ""Unit"": ""USD""}, ""UsageQuantity"": {""Amount"": ""20835"", ""Unit"": ""Hrs""}}, ""Groups"": [], ""Estimated"": false},{""TimePeriod"": {""Start"": ""2017-04-01"", ""End"": ""2017-05-01""}, ""Total"": {""UnblendedCost"": {""Amount"": ""2982.62609983"", ""Unit"": ""USD""}, ""UsageQuantity"": {""Amount"": ""21049"", ""Unit"": ""Hrs""}}, ""Groups"": [], ""Estimated"": false},{""TimePeriod"": {""Start"": ""2017-05-01"", ""End"": ""2017-06-01""}, ""Total"": {""UnblendedCost"": {""Amount"": ""1399.04829988"", ""Unit"": ""USD""}, ""UsageQuantity"": {""Amount"": ""23010"", ""Unit"": ""Hrs""}}, ""Groups"": [], ""Estimated"": false},{""TimePeriod"": {""Start"": ""2017-06-01"", ""End"": ""2017-07-01""}, ""Total"": {""UnblendedCost"": {""Amount"": ""962.47549987"", ""Unit"": ""USD""}, ""UsageQuantity"": {""Amount"": ""20049"", ""Unit"": ""Hrs""}}, ""Groups"": [], ""Estimated"": false}"; foreach (Match m in Regex.Matches(input, pattern)) { 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