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 = @"(?P<syslog_date>\S+\s+\d+\s+\d+:\d+:\d+)\s+0\s+(?P<log_date>\d+-\d+-\d+T\d+:\s\d+:\d+[^\s]+)\s+.*?(?:(?P<device>[^\s:]+)\s+)?(?P<application>ora_[^\s:]+_Audit)\s+-\s+-\s+Audit\[\d+\]:\s+(?:[^]]+]\s+)?(?:LENGTH:\s+\""(?P<length>\d+)\"".*?)?SESSIONID:(?:\[\d+\])?\s+\""(?P<sessionid>\d+)\"".*?ENTRYID:(?:\[\d+\])?\s+\""(?P<entryid>\d+)\"".*?(?:STATEMENT:(?:\[\d+\])?\s+\""(?P<statement>.*?)\"")?.*?USERID:(?:\[\d+\])?\s+\""(?P<userid>.*?)\"".*?(?:USERHOST:(?:\[\d+\])\s+""(?:(?P<host_domain>[^\\""]+)\\+)?(?P<userhost>[^""]*)"")?\s+(?:TERMINAL:(?:\[\d+\])\s+""(?P<terminal>[^""]*)""\s+)?ACTION:(?:\[\d+\])?\s+\""(?P<action>\d+)\"".*?RETURNCODE:(?:\[\d+\])?\s+\""(?P<code>.*?)\"".*?(?:COMMENT\$TEXT:(?:\[\d+\])?.*?\""Authenticated\s+by:\s+(?P<auth_by>\S+)(?:\;\s+Client\s+address:\s+\(ADDRESS\=\(PROTOCOL\=tcp\)\(HOST\=(?P<host>\d+\.\d+\.\d+\.\d+)\)\(PORT\=(?P<port>\d+)\)\).*?|""\s+)|OBJ\$CREATOR:(?:\[\d+\])?\s+\""(?P<objcreator>[^""]*)""\s+.*?OBJ\$NAME:(?:\[\d+\])?\s+\""(?P<objname>[^""]*)""\s+)OS\$USERID:(?:\[\d+\])?\s+\""(?P<osuserid>[^""]*)""\s*(?:(?!PRIV\$)\S+\s+)*(?:PRIV\$USED:(?:\[\d+\])?\s+""(?P<priv>[^""]*)"")?"; string input = @"Mar 31 00:02:54 0 2020-03-31T00: 02:53.629415+02:00 localhost ora_AM_Audit - - Audit[29579]: LENGTH: ""379"" SESSIONID:[9] ""130549450"" ENTRYID:[1] ""1"" STATEMENT:[1] ""1"" USERID:[15] ""EFACTURA_CDATOS"" USERHOST:[9] ""EFPRE-TRX"" ACTION:[3] ""100"" RETURNCODE:[1] ""0"" COMMENT$TEXT:[102] ""Authenticated by: DATABASE; Client address: (ADDRESS=(PROTOCOL=tcp)(HOST=192.168.200.237)(PORT=44530))"" OS$USERID:[9] ""efamerica"" DBID:[10] ""3787855415"" PRIV$USED:[1] ""5"" CURRENT_USER:[15] ""EFACTURA_CDATOS"""; 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