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

/
/
g

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"((?:(?# path without \"\" )(?<opening>(?# 'C:/', '//', '//./<UNC/C:>', '//?/<UNC/C:>' or '%VariableWindows%')(?<UNCPrefix>[\/\\][\/\\][?.][\/\\](?:UNC[\/\\])?)?(?<montage>\b[a-zA-Z]:[\/\\])|(?:(?:(?&UNCPrefix))|(?:[\/\\][\/\\](?!(?&montage))))|(?:%\w+%[\/\\]?))(?:(?# directory btw // )[^\/\\<>:\"|?\n\r ][^\/\\<>:\"|?\n\r]*(?<![ ])[\/\\])*(?:(?#we search for fileName only if next character is pathFriendly)(?=[^\/\\<>:\"'|?\n\r;, ])(?:(?#name file ? dir ?)(?:[^\/\\<>:\"|?\n\r;, .](?: (?=[\w\-]))?(?:\*(?!= ))?(?!(?&montage)))+)?(?:(?#extention)\.\w+)*))|(?:(?# path quoted \"\" or '' )[\"'](?&opening)(?=.*?[\"'])(?:[^\/\\<>:'\"|?\n\r]+[\/\\]?)+?[\"']))" test_str = ("\\\\LOCALHOST\\c$\\temp\\test-file.txt\"\n" "@\"c:\\temp\\test-file.txt\",\n" "@\"\\\\127.0.0.1\\c$\\temp\\test-file.txt\",\n" "@\"\\\\LOCALHOST\\c$\\ temp\\test-file.txt\",\n" "@\"\\\\.\\c:\\temp\\test-file.txt\",\n" "@\"\\\\?\\c:\\temp\\est-file.txt\",\n" "@\"\\\\.\\UNC\\LOCALHOST\\c$\\temp\\test-file.txt\",\n" "@\"\\\\127.0.0.1\\c$\\temp\\test-file.txt\"\n\n" "---------------------------\n" "Tentative d'accès à C:\\Users\\tpgz4017\\App - Data\\Local\\Temp\\tempShapeFile_CrossWave Calibration Zones - Atoll CrossWave Model.shx après sa fin.\n" "---------------------------\n\n" "file:///C:/Users/Downloads/20220516_32289275_1049383.pdf\n" "file://p-eco2.rd.fr/vol_H0037_01$/599/livraison/20220516_32289275_1049383.pdf\n" " --> couper les path apres le '\\ ', meme que on est arrivé au fichier\n" "c:\\temp\\test-file.txt\",\n" "\\\\127.0.0.1\\c$\\temp\\test-file.txt\",\n" "\\\\LOCALHOST\\c$\\ temp\\test-file.txt\",\n" "\\\\LOCALHOST\\c$ \\temp\\test-file.txt\",\n" "\\\\.\\c:\\temp\\t\\est-file.txt\",\n" "\\\\?\\c:\\temp\\test-file.txt\",\n" "\\\\.\\UNC\\LOCALHOST\\c$\\temp\\test-file.txt\",\n" "\\\\?\\UNC\\ServerName\\ temp\\test-file.txt\",\n" "\\\\127.0.0.1\\c$\\temp\\test-file.txt\"\n" "\\\\?\\server1\\e:\\utilities\\\\filecomparer\\\n\n" "C:/test\\gvk.hv/fgfjgjj bdsdfus(fg)\n" "C:/test\\gvkhv/../fgfjgjjb/yfigfi\n" "C:/test\\gvk.hv/fgfj.gjjb/uhloext C:/test\\gvk.hv/fgfj.gjjb/uhloext.ds\n" "C:/test\\gvk.hv/fgfj.gjjb/uhloext C:/UNC/test\\gvk.hv/fgfj.gjjb/uhloext.ds\n" "Site0 / 3: - Warning . See log file 'C:\\ProgramData\\InfoVista\\Planet 7.4\\7.4\\RPE\\Log\\Plugins\\Universal_Model_masked\\log_Universal_Model.txt' for details\n" "C:/test\\gvk.hv/fgfj.gjjb/uhloext.ds.yi : gf\n" "\\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Polygon\\Haguenau\\Building\\Haguenau hgtfhyt \"C:/te-st.html\" \"C:/te-st.html\" gd\"dhbcsk \"C:/te/dsst.ikpo fdsf \"C:\\test\" \"C:// test.html\" gd\n" "\"//te s t/e, llo.html \n" "C:/test\\f/uhlo/. \n" "C://te?st.html\n" "b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Custom Data\"\n" "; dfsdf \"\\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Custom Data\"\n" "; dfsdf \"\\\\\n" "Haguenau_Building.tab : Data format of \\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Polygon\\Haguenau\\Building\\Haguenau Building.* C: is invalid\n" "Haguenau_Building.tab : Data format of \\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo NetAct Atoll_Planet\\UR_Est\\Polygon\\Haguenau\\Building\\Haguenau Building.TAB, is invalid\n" "Haguenau_Building.tab : Data format of \\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Polygon\\Haguenau\\Building\\Haguenau Buildi*.*ng.*, is invalid\n" "C:/test/../hjgbkl C:/test/../hjgbkl.gfgdfgrdgfdgr C:/test/../hjgbkl\n" "C:/test.html\n" "C://test/ .h/hel,lo.html//test/./hello.html\n" "C:/test//hello.html\n" "//test\n" "//hello.html\n" "/test\n" "\"%tmp%/fsdfs\"\n" "%tmp%/fsdfs\n" "ERROR 8/31/2021 - 6:45:39 PM HighResClutter .RasterFile : \\\\b-ren ice\\sauv egardes\\B-HIER\\GEO%dsq%\\NewJersey_NewYork\\DTM\\DTM\\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil : Le fichier spécifié est introuvable. \n" "\\\\b-ren ice\\sauv egardes\\..\\B-HIER\\GEO\\NewJersey_NewYork\\DTM\\DTM\\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil C:\\b-ren ice\\sauv egardes\\B-HIER\\GEO\\NewJersey_NewYork\\DTM\\DTM\\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil \\\\b-ren ice\\sauv egardes\\B-HIER\\GEO\\NewJersey_NewYork\\DTM\\DTM\\CENTRAL_JER SE.Y_New_York_2 m_Z18N_0_DTM_02_06.bil. \n" "//test.html\n" "\\\\10.1.1.107\n" "//10.1.1.107/test.html\n" "//10.1.1.107/te st/hello.html\n" "//10.1.1.107/test/hello\n" "//test/hello.txt\n" "//test/hello.txt.\n" "/test/html\n" "/tes?t/html\n" "/test.html\n" "test.html\n" "//\n" "/\n" "\\\\\\rged\\bfg\n" "\\\\\n" "/t!esrtr\n" "C:/hel**o\n\n" "\\\\.\\UNC\\Server\\Share\\Test\\Foo.txt \n" "\\\\?\\UNC\\Server\\Share\\Test\\Foo.txt\n\n" "Pour les chemins UNC de périphérique, la partie serveur/partage forme le volume. Par exemple, dans \\\\?\\server1\\e:\\utilities\\\\filecomparer\\ , la partie serveur/partage est server1\\utilities . Ceci est important quand\n") matches = re.finditer(regex, test_str) 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