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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"^<(?<Direction>(Send|Recv)) TYPE=\"\"(?<Function>.+?)\"\" UTC=\"\"(?<date>.+?)\"\" ID=\"\"(?<ID>.+?)\"\"(?:\s*\/>|>(?<Message>.*?)<\/\1>)$", flags=re.DOTALL | re.IGNORECASE | re.MULTILINE) test_str = ("<Recv TYPE=\"Select.req\" UTC=\"05.11.2024 01:43:35\" ID=\"2130706432\" />\n" "<Send TYPE=\"Select.req\" UTC=\"05.11.2024 01:43:35\" ID=\"1152\" />\n" "<Send TYPE=\"Select.rsp\" UTC=\"05.11.2024 01:43:35\" ID=\"2130706432\" />\n" "<Send TYPE=\"S1F13W\" UTC=\"05.11.2024 01:43:35\" ID=\"1153\">\n" " <List Items=\"2\">\n" " <Ascii Size=\"17\" ItemName=\"MDLN\">SECSService</Ascii>\n" " <Ascii Size=\"20\" ItemName=\"SOFTREV\">1.0</Ascii>\n" " </List>\n" "</Send>\n" "<Recv TYPE=\"Select.rsp\" UTC=\"05.11.2024 01:43:35\" ID=\"1152\" />\n" "<Recv TYPE=\"S1F14\" UTC=\"05.11.2024 01:43:36\" ID=\"1153\">\n" " <List Items=\"2\">\n" " <Binary Size=\"4\">0x00</Binary>\n" " <List Items=\"0\" />\n" " </List>\n" "</Recv>\n" "<Recv TYPE=\"S1F13W\" UTC=\"05.11.2024 01:43:36\" ID=\"1\">\n" " <List Items=\"0\" />\n" "</Recv>\n" "<Send TYPE=\"S2F34\" UTC=\"05.11.2024 01:43:38\" ID=\"4\">\n" " <Binary Size=\"4\" ItemName=\"DRACK\">0x00</Binary>\n" "</Send>\n" "<Recv TYPE=\"S2F37W\" UTC=\"05.11.2024 01:43:39\" ID=\"5\">\n" " <List Items=\"2\">\n" " <Boolean Size=\"5\">False</Boolean>\n" " <List Items=\"17\">\n" " <UInt32 Size=\"1\">1</UInt32>\n" " <UInt32 Size=\"1\">2</UInt32>\n" " <UInt32 Size=\"1\">3</UInt32>\n" " <UInt32 Size=\"1\">5</UInt32>\n" " <UInt32 Size=\"1\">6</UInt32>\n" " <UInt32 Size=\"2\">10</UInt32>\n" " <UInt32 Size=\"2\">11</UInt32>\n" " <UInt32 Size=\"2\">20</UInt32>\n" " <UInt32 Size=\"2\">21</UInt32>\n" " <UInt32 Size=\"2\">22</UInt32>\n" " <UInt32 Size=\"2\">40</UInt32>\n" " <UInt32 Size=\"2\">41</UInt32>\n" " <UInt32 Size=\"2\">42</UInt32>\n" " <UInt32 Size=\"2\">50</UInt32>\n" " <UInt32 Size=\"2\">52</UInt32>\n" " <UInt32 Size=\"2\">70</UInt32>\n" " <UInt32 Size=\"2\">71</UInt32>\n" " </List>\n" " </List>\n" "</Recv>") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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