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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^\s*(lr_start_transaction.*\))\s*;\s*$"; string substitution = @"\1\);"; string input = @"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); "; RegexOptions options = RegexOptions.Multiline; Regex regex = new Regex(pattern, options); string result = regex.Replace(input, 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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx