Regular Expressions 101

Save & Share

  • Regex Version: ver. 5
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

/
/
gmu

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"(?<!検索結果：)(?<!次の)(?<![０-９0-9])(?<![０-９0-9][，,、])(?:[〇一二三四五六七八九十百千万億兆0-9０-９]|京+)[,，、]?.+[〇一二三四五六七八九十百千万億兆京0-9０-９].+件" test_str = ("Issue: with the original regex pattern, everything mathes (numbers + 件), but those that shouldn't partially match as you see below. \n\n\n" "******************************************\n" "*THESE BELOW SHOULD MATCH (just the numbers + 件)*\n\n" "販売実績100万件\n" "販売実績１００万件\n" "販売実績1,000件\n" "販売実績１，０００件\n" "販売実績1,000,000件です\n" "１００，０００件\n" "５０００件\n\n" "******************************************\n\n" "*BELOW PATTERNS SHOULD NOT MATCH*\n\n" "(☓)検索結果：１０件\n" "(x)検索結果：５００件\n" "(x)次の１００件\n" "(☓)１０件表示\n" "(☓)１０件を表示\n" "(☓)１０件の表示\n" "(x)全件\n\n" "(x)検索結果：１3953952件 <--- problem\n" "(x)検索結果：100,000,000件 <--- problem\n" "(x)検索結果：５０００件\n" "(x)次の５，０００件\n" "(x)次の５，００００件 <--- problem\n" "(x)次の１０００件\n" "(x)次の５万件") matches = re.finditer(regex, test_str, re.MULTILINE | re.UNICODE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.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