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

r"
"
gm

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('(?:\\d{1,3})\\s+(?:Platform Alarm\\(\\d+\\))\\s+\\d+\\s+(\\d+).+(\\d{4}-\\d{2}-\\d{2} \\d{2}:\\d{2}:\\d{2}).+nodeBId:(\\d+).+Office Name\\(Site\\)=([\\w_]+)', 'gm') const str = `277 Platform Alarm(20420) 1337 198092557 User-defined dry contact alarm 8 Minor SubNetwork=75,MEID=5721,Equipment=1,Rack=1,SubRack=1,Slot=13 2021-06-21 04:27:39 U RNCId: 75; Dry contact ID: 6; Board serial number: 274808900275; U nodeBId:5721 Office ID(Site)=5721/Office Name(Site)=San_Telmo/Alarm Object Type=SDR/Alarm Object ID=5721/Alarm Object Name=San_Telmo/Board Type=SA 75-5721-1_1_13_1_198092557_6 12 Radio Controller(1701) 100001 41591 1615258887314 Processing Alarm 83886256 NodeB is out of service Critical SubNet(75)/ManagedElement(75)/Rack No.(1)/Shelf No.(1)/Board No.(8)/CPU No.(1) 2021-03-29 20:08:33 Alarm Object:NODEB; \\nNodeB ID:5433; \\nAlarm sub code:2; \\nIub Transport bearer type:IP V4 Bearer Type; \\nLink Number:1; \\nLink ID list:1126;\\nLogic Position:System No.:0,Module No.:7,Index:0; RNCSCB04 83886768 NCP link failure Office ID(Site)=5433/Office Name(Site)=Tariba/Alarm Object Type=NODEB/Alarm Object ID=5433/Alarm Object Name=Tariba/Board Type=CDR/APP Type=product:wcdma,wcdma/Object MOC=UIUBLINK/Object DN=SubNetwork=75,MEID=75,URncFunction=75,UIubLink=5433 `; // 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