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"
"
gsx

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?sx)(?P<content>.*?) # Content up to next tag" & @CRLF & _ "(?P<markup> # Entire tag" & @CRLF & _ " <!\[CDATA\[(?P<cdata>.+?)]]>| # <![CDATA[ ... ]]>" & @CRLF & _ " <!--(?P<comment>.+?)-->| # <!-- Comment -->" & @CRLF & _ " </\s*(?P<close_tag>\w+)\s*>| # </tag>" & @CRLF & _ " <(?P<tag>\w+) # <tag ..." & @CRLF & _ " (?P<attributes>" & @CRLF & _ " (?P<attribute>\s+" & @CRLF & _ "# <snip>: Use this part to get the attributes out of 'attributes' group." & @CRLF & _ " (?P<attribute_name>\w+)" & @CRLF & _ " (?:\s*=\s*" & @CRLF & _ " (?P<attribute_value>" & @CRLF & _ " [\w:/.\-]+| # Unquoted" & @CRLF & _ " (?=(?P<_v> # Quoted" & @CRLF & _ " (?P<_q>['\"]).*?(?<!\\)(?P=_q)))" & @CRLF & _ " (?P=_v)" & @CRLF & _ " ))?" & @CRLF & _ "# </snip>" & @CRLF & _ " )*" & @CRLF & _ " )\s*" & @CRLF & _ " (?P<is_self_closing>/?) # Self-closing indicator" & @CRLF & _ " >) # End of tag" & @CRLF & _ "" Local $sString = "In this case, $url will indeed contain http://example.com/whatever.jpg. But what happens when you start getting HTML like this:" & @CRLF & _ "" & @CRLF & _ "<img src='http://example.com/whatever.jpg'>" & @CRLF & _ "or" & @CRLF & _ "" & @CRLF & _ "<img src=http://example.com/whatever.jpg>" & @CRLF & _ "or" & @CRLF & _ "" & @CRLF & _ "<img border=0 src="http://example.com/whatever.jpg">" & @CRLF & _ "or" & @CRLF & _ "" & @CRLF & _ "<img border src="http://example.com/whatever.jpg">" & @CRLF & _ "or" & @CRLF & _ "" & @CRLF & _ "<img" & @CRLF & _ " src="http://example.com/whatever.jpg">" & @CRLF & _ "or you start getting false positives from" & @CRLF & _ "" & @CRLF & _ "<!-- // commented out" & @CRLF & _ "<img src="http://example.com/outdated.png">" & @CRLF & _ "-->" & @CRLF & _ "" & @CRLF & _ "<script><![CDATA[ This is <b>not</b> parsed ]]></script>" & @CRLF & _ "" & @CRLF & _ "<asd ASD=asd>" & @CRLF & _ "" & @CRLF & _ "<!-- // commented out <img src="http://example.com/outdated.png"> -->" & @CRLF & _ "" & @CRLF & _ "No quotes:" & @CRLF & _ "<iframe src=test.html target=xyz></ iframe >" & @CRLF & _ "Self-closing tag:" & @CRLF & _ "<a href=test.html target=xyz/>" & @CRLF & _ "Self closing tag with a space before closure:" & @CRLF & _ "<a href=test.html target=xyz />" & @CRLF & _ "Double quotes:" & @CRLF & _ "<a href="test.html" target="xyz">" & @CRLF & _ "Single quotes:" & @CRLF & _ "<a href='test.html' target='xyz'>" & @CRLF & _ "Escaping double quotes:" & @CRLF & _ "<a href="test.html?val=1" title="\"No rules exist\" Andre Breton's quote">" & @CRLF & _ "Escaping single quotes (also with spaces between equals signs):" & @CRLF & _ "<a href = "test.html?val=1" title = 'Charlie\'s Angels'>" & @CRLF & _ "Tag without closure (ignored):" & @CRLF & _ "<a href = "test.html?val=1" title='Charlie\'s Angels'" & @CRLF & _ "Tag without opening (ignored):" & @CRLF & _ "a href = "test.html?val=1" title="Charlie\"s Angels">" & @CRLF & _ "" & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm