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

/
/
gmis

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 $sRegex = "(?mis)(?<!```html\s*)(<link href=.*?)(?=^\s*$)" Local $sString = "" & @CRLF & _ "# PATTERNS" & @CRLF & _ "" & @CRLF & _ "## Style Blocks (2 patterns)" & @CRLF & _ "- ***Matches:***" & @CRLF & _ " - All `<style> any code here </style> blocks that aren't preceded by ```css + any amount of optional whitespace" & @CRLF & _ "" & @CRLF & _ ">> NOTES FOR THE FOLLOWING PATTERN: " & @CRLF & _ " • This requires the `regex` library, not Python's built-in-crap" & @CRLF & _ " • This requires the `Single Line` (regex101) or `regex.DOTALL` (Python regex) flag" & @CRLF & _ "" & @CRLF & _ "### Pattern: Old version (would have replaced all punctuation with `punctuation` from the string library)" & @CRLF & _ " (?<!```css\s*)(\<style\>[\sa-z0-9\-\.\[\{\]\}:;#]+\<\/style\>)" & @CRLF & _ "" & @CRLF & _ ">> NOTES FOR THE FOLLOWING PATTERN: " & @CRLF & _ " • This requires the `regex` library, not Python's built-in-crap" & @CRLF & _ " • This requires the `Single Line` (regex101) or `regex.DOTALL` (Python regex) flag" & @CRLF & _ "" & @CRLF & _ "### Pattern: Newest version (much better)" & @CRLF & _ " (?<!```css\s*)(<style>.*?<\/style>)" & @CRLF & _ "" & @CRLF & _ "## This does the same thing but for `<!DOCTYPE html> any code here </html>`" & @CRLF & _ "" & @CRLF & _ ">> NOTES FOR THE FOLLOWING PATTERN: " & @CRLF & _ " • This requires the `regex` library, not Python's built-in-crap" & @CRLF & _ " • This requires the `Single Line` (regex101) or `regex.DOTALL` (Python regex) flag" & @CRLF & _ "" & @CRLF & _ "### Pattern:" & @CRLF & _ " (?<!```html\s*)(<!DOCTYPE html>.*?<\/html>)" & @CRLF & _ "" & @CRLF & _ "## This matches all blocks of code containing `<link href=>` up to, but not including, an empty line" & @CRLF & _ "" & @CRLF & _ ">> NOTES FOR THE FOLLOWING PATTERN: " & @CRLF & _ " • This requires the `regex` library, not Python's built-in-crap" & @CRLF & _ " • This requires the `Single Line` (regex101) or `regex.DOTALL` (Python regex) flag" & @CRLF & _ "" & @CRLF & _ "### Pattern:" & @CRLF & _ " (?<!```html\s*)(<link href=.*?)(?=^\s*$)" & @CRLF & _ "" & @CRLF & _ "<br>" & @CRLF & _ "" & @CRLF & _ "(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)(><)" & @CRLF & _ "" & @CRLF & _ "<br>" & @CRLF & _ "" & @CRLF & _ "# TEST TEXT" & @CRLF & _ "" & @CRLF & _ "<br>" & @CRLF & _ "" & @CRLF & _ "<style>" & @CRLF & _ " .list-group-mine .list-group-item {" & @CRLF & _ " background-color: black;" & @CRLF & _ " color: white;" & @CRLF & _ " border-top: 1px solid #0091b5;" & @CRLF & _ " border-left-color: #fff;" & @CRLF & _ " border-right-color: #fff;" & @CRLF & _ " }" & @CRLF & _ " .list-group-mine .list-group-item:hover {" & @CRLF & _ " background-color: red;" & @CRLF & _ " }" & @CRLF & _ "</style>" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "```css" & @CRLF & _ "<style>" & @CRLF & _ " .list-group-mine .list-group-item {" & @CRLF & _ " background-color: black;" & @CRLF & _ " color: white;" & @CRLF & _ " border-top: 1px solid #0091b5;" & @CRLF & _ " border-left-color: #fff;" & @CRLF & _ " border-right-color: #fff;" & @CRLF & _ " }" & @CRLF & _ " .list-group-mine .list-group-item:hover {" & @CRLF & _ " background-color: red;" & @CRLF & _ " }" & @CRLF & _ "</style>" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">" & @CRLF & _ "<div class="list-group list-group-mine">" & @CRLF & _ " <a class="list-group-item" href="https://bit.ly/3SICqay"><strong>Link to the SO Post</strong></a>" & @CRLF & _ " <a class="list-group-item" href="/path"><strong>Item 2</strong></a>" & @CRLF & _ " <a class="list-group-item" href="/path"><strong>Item 3</strong></a>" & @CRLF & _ "</div>" & @CRLF & _ "" & @CRLF & _ "<br>" & @CRLF & _ "" & @CRLF & _ "##### Before Bootstrap" & @CRLF & _ "<!DOCTYPE html>" & @CRLF & _ "" & @CRLF & _ "<html lang="en">" & @CRLF & _ " <head>" & @CRLF & _ " <title>TABLE</title>" & @CRLF & _ " </head>" & @CRLF & _ " <body>" & @CRLF & _ " <table>" & @CRLF & _ " <thead>" & @CRLF & _ " <tr>" & @CRLF & _ " <th>Name</th>" & @CRLF & _ " <th>Number</th>" & @CRLF & _ " </tr>" & @CRLF & _ " </thead>" & @CRLF & _ " <tbody>" & @CRLF & _ " <tr>" & @CRLF & _ " <td>Malachi</td>" & @CRLF & _ " <td>1-555-343-9867</td>" & @CRLF & _ " </tr>" & @CRLF & _ " <tr>" & @CRLF & _ " <td>Steve</td>" & @CRLF & _ " <td>1-555-734-8857</td>" & @CRLF & _ " </tr>" & @CRLF & _ " </tbody>" & @CRLF & _ " </table>" & @CRLF & _ " </body>" & @CRLF & _ "</html>" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "</br>" & @CRLF & _ "" & @CRLF & _ "<code style="color: #f51686; font-weight: bold; font-size: 16pt;"> The HTML </code>" & @CRLF & _ "" & @CRLF & _ "```html" & @CRLF & _ " <!DOCTYPE html>" & @CRLF & _ " <html lang="en">" & @CRLF & _ " <head>" & @CRLF & _ " <meta charset="UTF-8" />" & @CRLF & _ " <meta http-equiv="X-UA-Compatible" content="IE=edge" />" & @CRLF & _ " <meta name="viewport" content="width=device-width, initial-scale=1.0" />" & @CRLF & _ " <title>CSS Images</title>" & @CRLF & _ " <link rel="stylesheet" href="css/style.css" />" & @CRLF & _ " </head>" & @CRLF & _ "" & @CRLF & _ " <body>" & @CRLF & _ " <div class="container">" & @CRLF & _ " <section class="hero">" & @CRLF & _ " <figure class="profile-pic-figure">" & @CRLF & _ " <img" & @CRLF & _ " src="img/profile-800x800.png"" & @CRLF & _ " alt="profile"" & @CRLF & _ " width="800"" & @CRLF & _ " height="800"" & @CRLF & _ " title="Profile Pic"" & @CRLF & _ " />" & @CRLF & _ " <figcaption class="offscreen">Pookie Scrumptious</figcaption>" & @CRLF & _ " </figure>" & @CRLF & _ " <h1 class="h1">" & @CRLF & _ " <span class="nowrap">" & @CRLF & _ " Hello 👋" & @CRLF & _ " </span>" & @CRLF & _ " <span class="nowrap">" & @CRLF & _ " I'm Pookie" & @CRLF & _ " </span>" & @CRLF & _ " </h1>" & @CRLF & _ " </section>" & @CRLF & _ " </div>" & @CRLF & _ " </body>" & @CRLF & _ " </html>" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "<br>" & @CRLF & _ "" & @CRLF & _ "<code style="color: #f51686; font-weight: bold; font-size: 16pt;"> The CSS</code>" & @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