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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = #"^\s*(lr_start_transaction.*\))\s*;\s*$"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" lr_start_transaction(lr_eval_string("{scriptid}_0070_00000000_ASP-Hinzufuegen"); Siebel_SWECount_var -= 3; lr_save_int(Siebel_SWECount_var, "Siebel_SWECount"); web_save_timestamp_param("SiebelTimeStamp", LAST); web_add_cookie("SWEUAID=6; DOMAIN={domain}"); web_url("start.swe_60", "URL={url_start}?SWECmd=ShowPopupFrames&SWEDIC=1&SWEU={url_start}%3fSWECmd%3dGetCachedFrame%26SWEC%3d47%26SWEFrame%3dtop._sweclient._swecontent._sweview._swetmp%26SRN%3d{Siebel_SRN10}%26SWESP%3d1%26SRN%3d{Siebel_SRN10}&SRN={Siebel_SRN10}", "TargetFrame=", "Resource=0", "RecContentType=text/html", "Referer=", "Snapshot=t587.inf", "Mode=HTML", LAST); lr_end_transaction(lr_eval_string("{scriptid}_0070_00000000_ASP-Hinzufuegen"),LR_AUTO); lr_think_time(iThinktime); lr_start_transaction(lr_eval_string("{scriptid}_0080_00000000_ASP-Hinzufuegen-Eingabe"); Siebel_SWECount_var += 4; lr_save_int(Siebel_SWECount_var, "Siebel_SWECount"); web_reg_find("Text=Error","Search=Body", "Fail=Found", LAST); web_submit_data("start.swe_61", "Action={url_start}", "Method=POST", "TargetFrame=", "RecContentType=text/html", "Referer=", "Snapshot=t588.inf", "Mode=HTML", "EncodeAtSign=YES", ITEMDATA, "Name=SWEC", "Value={Siebel_SWECount}", ENDITEM, "Name=SWEMethod", "Value=UpdatePrefMsg", ENDITEM, "Name=SWERPC", "Value=1", ENDITEM, "Name=SWECmd", "Value=InvokeMethod", ENDITEM, "Name=SRN", "Value={Siebel_SRN10}", ENDITEM, "Name=SWEIPS", "Value=@0*0*1*0*0*3*0*5*SWEBS1*1", ENDITEM, "Name=SWEBS", "Value=1", ENDITEM, "Name=SWEService", "Value=Message Bar", ENDITEM, LAST); """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"\1\);"# let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString) print(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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression