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

Substitution
Processing...

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?mis)<a \s+ ((?:[^\s<>'"=]+(?:=(?:"[^"]*"|'[^']*'|[^\s'">]+))?\s+)*) href=(?|"([^"]*\.(?:jpe?g|png))"|'([^']*\.(?:jpe?g|png))'|([^\s'">]*\.(?:jpe?g|png))(?=[>\s])) ((?:\s+[^\s<>'"=]+(?:=(?:"[^"]*"|'[^']*'|[^\s'">]+))?)*) \s*> (.*?) </a>`) var str = `<p>С этой формы приходят заявки <a href="https://site.com/lack_tech.php">https://site.com/lack_tech.php</a></p> <p>Или что ты имеешь ввиду?</p> <div class="attachment_files_message"> <p>Прикреплённые файлы:</p> <a href="http://site.com/public/uploads/kylticket/2670/Screenshot_1.png" target="_blank">Screenshot_1.png</a> <a href=http://site.com/public/uploads/kylticket/2670/Screenshot_1.png target="_blank">Screenshot_1.png</a> <a target="_blank" href="http://site.com/public/uploads/kylticket/2670/Screenshot_1.png" >Screenshot_1.png</a> </div>` var substitution = "<a $1$3 data-fancybox="gallery" href="$2"><img src="$2" alt="" class="tmp_class"></a>" fmt.Println(re.ReplaceAllString(str, substitution)) }

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 Golang, please visit: https://golang.org/pkg/regexp/