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

use strict; my $str = '<?xml version="1.0" encoding="UTF-8"?> -<Devices-Detail-Response xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.embeddeddatasystems.com/schema/owserver"> <PollCount>71</PollCount> <DevicesConnected>2</DevicesConnected> <LoopTime>2.048</LoopTime> <DevicesConnectedChannel1>2</DevicesConnectedChannel1> <DevicesConnectedChannel2>0</DevicesConnectedChannel2> <DevicesConnectedChannel3>0</DevicesConnectedChannel3> <DataErrorsChannel1>0</DataErrorsChannel1> <DataErrorsChannel2>0</DataErrorsChannel2> <DataErrorsChannel3>0</DataErrorsChannel3> <VoltageChannel1>4.81</VoltageChannel1> <VoltageChannel2>4.81</VoltageChannel2> <VoltageChannel3>4.80</VoltageChannel3> <VoltagePower>5.05</VoltagePower> <DeviceName>OWServer_v2-Enet</DeviceName> <HostName>EDSOWSERVER2</HostName> <MACAddress>00:04:A3:BE:A9:F2</MACAddress> <DateTime>2017-03-10 23:18:40</DateTime> -<owd_DS18B20 Description="Programmable resolution thermometer"> <Name>DS18B20</Name> <Family>28</Family> <ROMId>690516B3FC14FF28</ROMId> <Health>7</Health> <Channel>1</Channel> <RawData>54014B467FFF0C10FDFF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000</RawData> <PrimaryValue>21.2500 Deg C</PrimaryValue> <Temperature Units="Centigrade">21.2500</Temperature> <UserByte1 Writable="True">75</UserByte1> <UserByte2 Writable="True">70</UserByte2> <Resolution>12</Resolution> <PowerSource>255</PowerSource> </owd_DS18B20> -<owd_DS18B20 Description="Programmable resolution thermometer"> <Name>DS18B20</Name> <Family>28</Family> <ROMId>020316B4A6C3FF28</ROMId> <Health>7</Health> <Channel>1</Channel> <RawData>55014B467FFF0C10BEFF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000</RawData> <PrimaryValue>21.3125 Deg C</PrimaryValue> <Temperature Units="Centigrade">21.3125</Temperature> <UserByte1 Writable="True">75</UserByte1> <UserByte2 Writable="True">70</UserByte2> <Resolution>12</Resolution> <PowerSource>255</PowerSource> </owd_DS18B20> </Devices-Detail-Response>'; my $regex = qr/<RawData>55014B467FFF0C10BEFF00+<\/RawData>\n\n<PrimaryValue>(\d+.\d+)/p; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html