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 = @"\""user\"":\s+\{\s+\""id\"":\s+(?<user_id>[^,]+)"; string input = @"""aepassword"": ""kmdAkcu)n>Ec_.a(m5P7?8-n"", ""aeci"": { ""outgoing_server"": ""mailrv.aaa.com"", ""email_footer"": ""C:\\ProgramData\\bbb\\AutomationNote\\Email\\aa_Mail_Footer.png"", ""email_header"": ""C:\\ProgramData\\bbb\\AutomationNote\\Email\\aa_Mail_Header.png"", ""signature"": ""C:\\ProgramData\\bbb\\Automation\\Email\\bb_Email_Signature.txt"", ""requires_authentication"": ""false"", ""reply-to"": ""us@aaa.com"", ""primaryaddress"": ""ussdev@aaa.com"", ""host"": ""ussdev@bbb.com"", ""entity_alternate_names"": ""usdev@aaa.com"", ""outgoing_port"": ""2675"", ""entityid"": ""wmid-1607548215055521"", ""name"": ""bbb_MailBox"", ""entitytype"": ""Sub-System"", ""entitytype"": ""Workplace"", ""technology"": ""O736i85"", ""tenantid"": 1000011, ""cloudprovider"": "", ""satellite"": ""sat-16107579705752592"", ""resourceid"": null, ""UDetails"": { ""creds"": { ""email"": ""NA"" }, ""id"": 14, ""name"": ""N/A"" }, ""encryptionKey"": ""5inqhg7ckj7klk2w4osk0"", ""user"": { ""id"": 5, ""name"": ""CRI Admin"", ""employeecode"": ""125"", ""email"": ""admin@aaa.com"" },"; 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