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

/
/

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"<\d+>\S+\s(\d{4}-\d{2}-\d{2})\s(\d{2}\x3a\d{2}\x3a\d{2}),\d+\s\x5b\d+\x5d\s+\S+\s+\S+\s\S+\s+\S+\s+\S+\s\S+\s\ServerIPAddress\x3a\s\S+\s((?:\d{1,3}\x2e){3}\d{1,3})\s+ClientIPAddress\x3a\s(\S+)\s\S+\s\S+\s\S+\s\S+\s+\S+\s\S+\s+\S+\s\S+\s+\S+\s\S+\s+\S+\s+\S+\s+MessageText\x3a\s(Admin\sActivity)\s+UserId\x3a\s(\d+)\s+UserName\x3a\s(\S+)\s+Action\sDate\/Time\x3a\s+\S+\s\S+\s\S+\s+Portal\sGroup\sId\x3a\s(\d+)\s+Portal Group Name\x3a\s([a-zA-Z\s]+)\s+Action\sType\x3a\s([a-zA-Z\s]+)\sAction\sDetail\x3a([a-zA-Z0-9\.\;\s\:]+)\sArea\sOf\sAdministration\x3a\s(\S+)\s+Portal\sId\x3a\s(\d+)\s+Portal\sName\x3a\s([a-zA-Z0-9\s]+)\s+Enterprise\sUser\x3a\s(\S+)" test_str = ("<190>MedSeekBusinessServer.exe: 2016-08-08 09:04:06,965 [4] INFO MedSeek.Portal.Server.LoggingProvider.Data.AuditTrailSqlDao UserID: -9999 UserName: System ServerIPAddress: 10.247.82.26 10.247.82.112 ClientIPAddress: (null) PortalId: (null) PortalName: (null) AssemblyName: MedSeek.Portal.Server.LoggingProvider\n" " ClassName: AuditTrailSqlDao\n" " MethodName: LogToSysLog\n" " CustomProps: 6ZalfDCycQw=\n" " MessageText: Admin Activity\n" " UserId: 301640\n" " UserName: myost6\n" " Action Date/Time: 8/8/2016 1:04:06 PM\n" " Portal Group Id: 1273153\n" " Portal Group Name: myCarolinas Admin\n" " Action Type: Update User\n" " Action Detail: User updated. User ID: 301640; UserName: myost6; \n" " Area Of Administration: Users\n" " Portal Id: 6\n" " Portal Name: my Carolinas Mobile\n" " Enterprise User: False\n" "<190>MedSeekBusinessServer.exe: 2016-08-08 09:04:06,965 [4] INFO MedSeek.Portal.Server.LoggingProvider.Data.AuditTrailSqlDao UserID: -9999 UserName: System ServerIPAddress: 10.247.82.26 10.247.82.112 ClientIPAddress: (null) PortalId: (null) PortalName: (null) AssemblyName: MedSeek.Portal.Server.LoggingProvider\n" " ClassName: AuditTrailSqlDao\n" " MethodName: LogToSysLog\n" " CustomProps: 6ZalfDCycQw=\n" " MessageText: Admin Activity\n" " UserId: 301640\n" " UserName: myost6\n" " Action Date/Time: 8/8/2016 1:04:06 PM\n" " Portal Group Id: 1273153\n" " Portal Group Name: myCarolinas Admin\n" " Action Type: Update User\n" " Action Detail: User updated. User ID: 301640; UserName: myost6; \n" " Area Of Administration: Users\n" " Portal Id: 6\n" " Portal Name: my Carolinas Mobile\n" " Enterprise User: False \n" "<190>MedSeekBusinessServer.exe: 2016-08-08 09:04:12,815 [4] INFO MedSeek.Portal.Server.LoggingProvider.Data.AuditTrailSqlDao UserID: -9999 UserName: System ServerIPAddress: 10.247.82.26 10.247.82.112 ClientIPAddress: (null) PortalId: (null) PortalName: (null) AssemblyName: MedSeek.Portal.Server.LoggingProvider\n" " ClassName: AuditTrailSqlDao\n" " MethodName: LogToSysLog\n" " CustomProps: 6ZalfDCycQw=\n" " MessageText: Admin Activity\n" " UserId: 244010\n" " UserName: katdbod\n" " Action Date/Time: 8/8/2016 1:04:12 PM\n" " Portal Group Id: 1273153\n" " Portal Group Name: myCarolinas Admin\n" " Action Type: Update User\n" " Action Detail: User updated. User ID: 244010; UserName: katdbod; \n" " Area Of Administration: Users\n" " Portal Id: 2\n" " Portal Name: myCarolinas\n" " Enterprise User: False\n" "<190>MedSeekBusinessServer.exe: 2016-08-08 09:04:12,815 [4] INFO MedSeek.Portal.Server.LoggingProvider.Data.AuditTrailSqlDao UserID: -9999 UserName: System ServerIPAddress: 10.247.82.26 10.247.82.112 ClientIPAddress: (null) PortalId: (null) PortalName: (null) AssemblyName: MedSeek.Portal.Server.LoggingProvider%0D ClassName: AuditTrailSqlDao%0D MethodName: LogToSysLog%0D CustomProps: 6ZalfDCycQw=%0D MessageText: Admin Activity%0D UserId: 244010%0D UserName: katdbod%0D Action Date/Time: 8/8/2016 1:04:12 PM%0D Portal Group Id: 1273153%0D Portal Group Name: myCarolinas Admin%0D Action Type: Update User%0D Action Detail: User updated. User ID: 244010; UserName: katdbod; %0D Area Of Administration: Users%0D Portal Id: 2%0D Portal Name: myCarolinas%0D Enterprise User: False%0D \n" "<190>MedSeekBusinessServer.exe: 2016-08-08 09:04:12,971 [4] INFO MedSeek.Portal.Server.LoggingProvider.Data.AuditTrailSqlDao UserID: -9999 UserName: System ServerIPAddress: 10.247.82.26 10.247.82.112 ClientIPAddress: (null) PortalId: (null) PortalName: (null) AssemblyName: MedSeek.Portal.Server.LoggingProvider%0D ClassName: AuditTrailSqlDao%0D MethodName: LogToSysLog%0D CustomProps: 6ZalfDCycQw=%0D MessageText: Admin Activity%0D UserId: 244010%0D UserName: katdbod%0D Action Date/Time: 8/8/2016 1:04:12 PM%0D Portal Group Id: 1273153%0D Portal Group Name: myCarolinas Admin%0D Action Type: Update User%0D Action Detail: User updated. User ID: 244010; UserName: katdbod; %0D Area Of Administration: Users%0D Portal Id: 2%0D Portal Name: myCarolinas%0D Enterprise User: False%0D \n" "<190>MedSeekBusinessServer.exe: 2016-08-08 09:04:12,971 [4] INFO MedSeek.Portal.Server.LoggingProvider.Data.AuditTrailSqlDao UserID: -9999 UserName: System ServerIPAddress: 10.247.82.26 10.247.82.112 ClientIPAddress: (null) PortalId: (null) PortalName: (null) AssemblyName: MedSeek.Portal.Server.LoggingProvider%0D ClassName: AuditTrailSqlDao%0D MethodName: LogToSysLog%0D CustomProps: 6ZalfDCycQw=%0D MessageText: Admin Activity%0D UserId: 244010%0D UserName: katdbod%0D Action Date/Time: 8/8/2016 1:04:12 PM%0D Portal Group Id: 1273153%0D Portal Group Name: myCarolinas Admin%0D Action Type: Update User%0D Action Detail: User updated. User ID: 244010; UserName: katdbod; %0D Area Of Administration: Users%0D Portal Id: 2%0D Portal Name: myCarolinas%0D Enterprise User: False%0D \n" "<190>MedSeekBusinessServer.exe: 2016-08-08 09:04:33,766 [4] INFO MedSeek.Portal.Server.LoggingProvider.Data.AuditTrailSqlDao UserID: -9999 UserName: System ServerIPAddress: 10.247.82.26 10.247.82.112 ClientIPAddress: (null) PortalId: (null) PortalName: (null) AssemblyName: MedSeek.Portal.Server.LoggingProvider%0D ClassName: AuditTrailSqlDao%0D MethodName: LogToSysLog%0D CustomProps: 6ZalfDCycQw=%0D MessageText: Admin Activity%0D UserId: 164664%0D UserName: rrrleigh%0D Action Date/Time: 8/8/2016 1:04:33 PM%0D Portal Group Id: 1273153%0D Portal Group Name: myCarolinas Admin%0D Action Type: Change User Password%0D Action Detail: Password changed for user. User ID: 164664; %0D Area Of Administration: Users%0D Portal Id: 2%0D Portal Name: myCarolinas%0D Enterprise User: False%0D \n" "<190>MedSeekBusinessServer.exe: 2016-08-08 09:04:33,766 [4] INFO MedSeek.Portal.Server.LoggingProvider.Data.AuditTrailSqlDao UserID: -9999 UserName: System ServerIPAddress: 10.247.82.26 10.247.82.112 ClientIPAddress: (null) PortalId: (null) PortalName: (null) AssemblyName: MedSeek.Portal.Server.LoggingProvider%0D ClassName: AuditTrailSqlDao%0D MethodName: LogToSysLog%0D CustomProps: 6ZalfDCycQw=%0D MessageText: Admin Activity%0D UserId: 164664%0D UserName: rrrleigh%0D Action Date/Time: 8/8/2016 1:04:33 PM%0D Portal Group Id: 1273153%0D Portal Group Name: myCarolinas Admin%0D Action Type: Change User Password%0D Action Detail: Password changed for user. User ID: 164664; %0D Area Of Administration: Users%0D Portal Id: 2%0D Portal Name: myCarolinas%0D Enterprise User: False%0D \n") matches = re.search(regex, test_str) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html