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

Generated Code

$re = '/(\w+)=(\w+)/m'; $str = '{ "request": "START_SIGNATURE", "request_id": "9876543210", "user": "{{user}}", "password": "{{password}}", "signature": { "config_id": 12345, "contract_id": "CompanyID1233456", "level": [ { "level_order": 0, "required_signatories_to_complete_level": 2, "signatories": [ { "phone": "+34666666666", "email": "signatory1@gmail.com", "name": "Nombre1", "surname": "Apellido1", "position_id": "1" }, { "phone": "+34677777777", "email": "signatory2@gmail.com", "name": "Nombre2", "surname": "Apellido2", "upload_files_registered": "Y", "position_id": "2", "upload_files": [ { "name": "Foto DNI", "optional": "Y" } ] } ] }, { "level_order": 1, "required_signatories_to_complete_level": 1, "signatories": [ { "phone": "+34688888888", "email": "signatory3@gmail.com", "name": "Nombre3", "surname": "Apellido3", "position_id": "3" } ] } ], "file": [ { "filename": "contract.pdf", "content": "{{base64_file_content}}", "file_group": "contract_files", "signature_position": [ { "signatory_position_id": "1", "page": "all", "x": 40.0, "y": 50.0, "height": 20, "width": 30, "rotation": 0 }, { "signatory_position_id": "2", "page": "4", "x": 80.0, "y": 50.0, "height": 20, "width": 30, "rotation": 0 }, { "signatory_position_id": "3", "page": "last", "x": 60.0, "y": 120.0 } ] } ] } }'; $subst = "\"$1\":\"$2\","; $result = preg_replace($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