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

@"
"
sgim

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('^<(?<Direction>(Send|Recv)) TYPE=""(?<Function>.+?)"" UTC=""(?<date>.+?)"" ID=""(?<ID>.+?)""(?:\\s*\\/>|>(?<Message>.*?)<\\/\\1>)$', 'sgim') const str = `<Recv TYPE="Select.req" UTC="05.11.2024 01:43:35" ID="2130706432" /> <Send TYPE="Select.req" UTC="05.11.2024 01:43:35" ID="1152" /> <Send TYPE="Select.rsp" UTC="05.11.2024 01:43:35" ID="2130706432" /> <Send TYPE="S1F13W" UTC="05.11.2024 01:43:35" ID="1153"> <List Items="2"> <Ascii Size="17" ItemName="MDLN">SECSService</Ascii> <Ascii Size="20" ItemName="SOFTREV">1.0</Ascii> </List> </Send> <Recv TYPE="Select.rsp" UTC="05.11.2024 01:43:35" ID="1152" /> <Recv TYPE="S1F14" UTC="05.11.2024 01:43:36" ID="1153"> <List Items="2"> <Binary Size="4">0x00</Binary> <List Items="0" /> </List> </Recv> <Recv TYPE="S1F13W" UTC="05.11.2024 01:43:36" ID="1"> <List Items="0" /> </Recv> <Send TYPE="S2F34" UTC="05.11.2024 01:43:38" ID="4"> <Binary Size="4" ItemName="DRACK">0x00</Binary> </Send> <Recv TYPE="S2F37W" UTC="05.11.2024 01:43:39" ID="5"> <List Items="2"> <Boolean Size="5">False</Boolean> <List Items="17"> <UInt32 Size="1">1</UInt32> <UInt32 Size="1">2</UInt32> <UInt32 Size="1">3</UInt32> <UInt32 Size="1">5</UInt32> <UInt32 Size="1">6</UInt32> <UInt32 Size="2">10</UInt32> <UInt32 Size="2">11</UInt32> <UInt32 Size="2">20</UInt32> <UInt32 Size="2">21</UInt32> <UInt32 Size="2">22</UInt32> <UInt32 Size="2">40</UInt32> <UInt32 Size="2">41</UInt32> <UInt32 Size="2">42</UInt32> <UInt32 Size="2">50</UInt32> <UInt32 Size="2">52</UInt32> <UInt32 Size="2">70</UInt32> <UInt32 Size="2">71</UInt32> </List> </List> </Recv>`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions