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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(租赁)?.{0,9}确认(为)?使用权资产" test_str = ("租赁期开始日，本公司对租赁确认使用权资产和租赁负债\n" "租赁期开始日，对租赁确认使用权资产和租赁负债\n" "本公司对租赁确认使用权资产和租赁负债。\n" "本集团在租赁期开始日对租赁确认使用权资产和租赁负债\n" "公司对租赁确认使用权资产和租赁负债\n" "本公司对租赁确认使用权资产和租赁负债\n" "本公司对租赁确认使用权资产和租赁负债\n" "在租赁期开始日，本公司对租赁确认使用权资产和租赁负债\n" "在租赁期开始日，公司对租赁确认使用权资产和租赁负债。\n" "在租赁期开始日，公司对租赁确认使用权资产和租赁负债\n" "本公司选择确认使用权资产和租赁负债，\n" "本公司对租赁确认使用权资产和租赁负债。\n" "对租赁确认使用权资产和租赁负债\n" "本公司对租赁确认使用权资产和租赁负债。\n" "确认使用权资产和租赁负债\n" "本集团对租赁确认使用权资产和租赁负债\n" "确认为使用权资产，确认为租赁负债\n" "本公司对租赁确认使用权资产和租赁负债\n" "在租赁期开始日，公司对租赁确认使用权资产和租赁负债\n" "公司租入资产所支付的租赁费，在不扣除免租期的整个租赁期内，按直线法进行分摊，计入当期费用\n" "在租赁期开始日，公司对租赁确认使用权资产和租赁负债\n" "在租赁期开始日，公司对租赁确 认使用权资产和租赁负债\n" "在租赁期开始日，本公司对租赁确认使用权资产，确认租赁负债。\n" "在租赁期开始日，公司对租赁确认使用权资产和租赁负债\n" "本集团在租赁期开始日对租赁确认使用权资产,租赁负债\n" "在租赁期开始日，公司对租赁确认使用权资产和租赁负债。\n") matches = re.finditer(regex, test_str, re.MULTILINE) 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