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

/
/
gmi

Test String

Code Generator

Language

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?mi)(?<!&)(?:\b(?:[a-z]{2,8}\d{0,2})|#[0-9a-f]+);" Local $sString = "I have a huge HTML with several special chars, in the forms &nbsp; or "&#82173333;." & @CRLF & _ "Faulty HEX: #82173333;" & @CRLF & _ "Some of them are wrong, because they lack the initial &." & @CRLF & _ "" & @CRLF & _ "I would like to search for such wrong spacial chars. I know that I can search all the right special chars by means of the following regex:" & @CRLF & _ "" & @CRLF & _ " \&(?:[a-z]+|#x?\d+);\" & @CRLF & _ "But I'd need a regex useful to search the wrong ones (without the initial &). Can you help me? Thanks in advance" & @CRLF & _ "" & @CRLF & _ "Edit:" & @CRLF & _ "" & @CRLF & _ "As suggested, I post an example. My HTML cointains the following statement:" & @CRLF & _ "" & @CRLF & _ " <![CDATA[<nolink>blablabla&nbsp;blablabla</nolink>]]>nbsp;" & @CRLF & _ "where we have 2 special HTML character:" & @CRLF & _ "divide;" & @CRLF & _ "&divide;" & @CRLF & _ "&nbsp;" & @CRLF & _ "quot;" & @CRLF & _ "I'm interested in finding the second item, because it is wrong (laking the initial &)." & @CRLF & _ "" & @CRLF & _ "So the output of the requested regex should be: quot;" 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