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"((?<=\[)\w+)(?#匹配宏名称)|(\w+(?=\=))(?#匹配参数名称)|((?<=\=)\d+)(?#匹配int参数)|((?<=\=)\[\d+,\d+\])(?#匹配长度为2的int数组)|((?<=\=)\[\d+,\d+,\d+,\d+])(?#匹配长度为4的int数组)|(\"[a-zA-Z\._0-9\s]+\")(?#匹配使用双引号的string参数)|(\'[a-zA-Z\._0-9\s]+\')(?#匹配使用单引号的string参数)" test_str = ("//完整代码匹配测试\n" "[sprite file=\"1.png\" index=2 rect=[20,20,800,600] pos=[800,600]][sprite file='2.png' index=2 rect=[0,0,0,0]] //这是注释 abcd\n" "//宏名称单元测试\n" "[bg]\n" " [bg]\n" "[ bg]\n\n" "//字符串参数值单元测试\n" "=\"abc\"\n" "=\"ABC\"\n" "=\"_abcABC\"\n" "=\"_abcABC.png\"\n" "=\"_abcABC special.png\" \n\n" "//参数名单元测试\n" "[bg index=2]\n" "[bg index=2]\n" "[bg index =2]\n\n" "//int参数值单元测试\n" "[bg index=54687]\n" "[bg index=1 index2=26764]\n" "//pos_t 4位长度的int数组测试\n" "[bg index=0 pos=[1,2,3,4]]\n" "//匹配坐标型 pos_t指长度为2的整数型数组，分别为横坐标x、纵坐标y\n" "[bg index=0 pos=[0,2]\n" "//匹配注释") 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