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

/
/
gm

Test String

Substitution

Processing...

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"<([a-zA-Z\d]+?)([^<>]|(?!.*href).*)>([^<>]*?)(小编)([^<>]*?)(<\/\1>)" test_str = ("<p>\n" " <link rel=\"stylesheet\" href=\"/public/lib/froala/css/froala_style.min.css\">\n" "</p>\n\n" "<span>高校在线教学国际平台建设启动？这是怎么回事呢？下面就跟小编一起来了解一下事情的始末吧！</span>\n\n" "<a href=\"\">高校在线教学国际平台建设启动？这是怎么回事呢？下面就跟小编一起来了解一下事情的始末吧！</a>\n\n" "<p><span style='color: rgb(34, 34, 34); font-family: Consolas, \"Lucida Console\", \"Courier New\", monospace; font-size: 12px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;'>高校在线教学国际平台建设启动？这是怎么回事呢？下面就跟小编一起来了解一下事情的始末吧！</span>&nbsp;</p>\n\n" "<span style='color: rgb(34, 34, 34); font-family: Consolas, \"Lucida Console\", \"Courier New\", monospace; font-size: 12px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-style: initial; text-decoration-color: initial; display: inline !important; float: none;'>以上就是小编给大家分享的相关情况介绍，希望对大家有所帮助！最后，小编送大家一句话：当许多人在一条路上徘徊不前时，他们不得不让开一条大路，让那珍惜时间的人赶到他们的前面去。&mdash;&mdash;苏格拉底</span>") subst = "<$1$2>$3<a href=\"{link}\" target=\"_blank\">$4</a>$5$6'" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # 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