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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/(?i)\[\[(?<firstlevelfolder>(?:assets|Bücher|Dokument|epsilon_notes|kontakte|literatur|Projekt|Test|Wissen|WV)(?:[\w_]*)\/)(?<bildpfad>[^\|\\\\\]]+)(\\\\\||\|)*(?<bildattribut>[^\]]*)\]\]/m'; $str = 'Link zum Bild: ![[Projekte/Mikroskop/_resources/f04ae6b6a924e20e761dce25603b3bd8.jpg]] ![[assets/(15) Bigger Arms Workout (Dumbbells Only) - YouTube - 3 34.jpeg]] ![[subfolder/image.png|100x100]] ![[subfolder/sub2/image.png|100x100]] ![[../../ima/ge.png|100x100]] [[Dokumente/Gesundheit/Dave/_Dave_overview]] ![[Projekte/image.png|100x100]] ![[Projekte_irgendwas/image.Png|100x100]] [[assets/MiSZ 2T.pdf]] [[assets2/MiSZ 2T.pdf]] ![[Projekte/Mikroskop/Leica, Wild/Product Guide for Stereomicroscopes. Living up to Life.pdf]] ![[BA_GSZ 2_GSZ 2T.pdf#page=7]] ![[BA_GSZ 2_GSZ 2T.pdf]] Beispiel-tabelle: Caption1 | Caption2 | ---|---| Content1 text | Link innerhalb Tabelle mit Attributen ![[Projekte/Mikroskop/_resources/f04ae6b6a924e20e761dce25603b3bd8.jpg\\|300]] | vorerst letzte Zeile | Text Text Text | ![[Projekte/Mikroskop/_resources/f04ae6b6a924e20e761dce25603b3bd8.jpg\\|200]]'; $subst = "[<span style=\"color:blue\">CPLinkToFile: </span> <span style=\"background-color: #caecff; color:blue\">**${firstlevelfolder}${bildpfad}**</span>](/storage/emulated/0/onedrive/obsidian/${firstlevelfolder}${bildpfad})"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$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 PHP, please visit: http://php.net/manual/en/ref.pcre.php