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

`
`
gmi

Test String

Substitution

Processing...

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"((?<field>[a-z0-9]*)=>)(?<value>""[a-z0-9-_'/=> ]*"")"; string substitution = @"'${field}' => ${value},"; string input = @"FldSelectAllowAdd=>""0"" FldSelectFilter=>"" FldSelectFilterFld=>"" FldSelectForceSelection=>""0"" FldSelectMultiple=>""0"" FldSelectSize=>"" FldSelectType=>""Values"" FldTagLnkDisp2=>"" FldTagLnkDisplay=>"" FldTagLnkDistinct=>""0"" FldTagLnkFld=>"" FldTagLnkOrderBy=>"" FldTagLnkOrderType=>"" FldTagLnkTbl=>"" FldTagAPrefix=>""None"" FldTagASuffix=>"" FldTagATarget=>"" FldTagAType=>"" FldTagCols=>"" FldTagHiddenValue=>"" FldTagImgHeight=>"" FldTagImgWidth=>"" FldTagMaxLength=>"" FldTagRows=>"" FldTagSize=>"" FldTagValues=>"" FldAdd=>""0"" FldAddOpt=>""1"" FldAggregate=>"" FldAjax=>""0"" FldAlias=>""0"" FldAlign=>"" FldAlt=>"" FldAttribute=>""100"" FldAutoFill=>""0"" FldAutoIncrement=>""0"" FldAutoUpdateValue=>"" FldBasicSearch=>""0"" FldBold=>""0"" FldCaption=>""Updated At"" FldCheckDuplicate=>""0"" FldColumnWidth=>"" FldColumnWrap=>""0"" FldDefault=>"" FldDtFormat=>""7"" FldEdit=>""0"" FldEditCustomAttributes=>"" FldEditTableField=>"" FldErrMsg=>"" FldExport=>""0"" FldExtendedBasicSearch=>""0"" FldFmtType=>""Date/Time"" FldGenerate=>""1"" FldGpDigits=>""-2"" FldGroupBy=>""0"" FldGroupByShowSummary=>""0"" FldHrefFld=>"" FldHrefFldOrig=>""0"" FldHtmlTag=>""TEXT"" FldHtmlTagReadOnly=>""0"" FldIncLeadDigit=>""-2"" FldIsPrimaryKey=>""0"" FldItalic=>""0"" FldList=>""0"" FldMax=>"" FldMemoCRLFReplace=>""0"" FldMemoMaxLength=>""0"" FldMin=>"" FldMultiUpdate=>""0"" FldNumDigits=>""0"" FldOrder=>"" FldOrderBy=>""0"" FldPageIndex=>""1"" FldParentSelect=>"" FldPopCalendar=>""0"" FldQuoteE=>""'"" FldQuoteS=>""'"" FldRegister=>""0"" FldRepeatColumns=>""0"" FldReq=>""0"" FldRequired=>""0"" FldResizeHeight=>""0"" FldResizeQuality=>""75"" FldResizeWidth=>""0"" FldRptAggAvg=>""0"" FldRptAggMax=>""0"" FldRptAggMin=>""0"" FldRptAggSum=>""0"" FldSearch=>""0"" FldSize=>""26"" FldSourceField=>"" FldSourceName=>"" FldSourceTable=>"" FldSrchOpr=>""=>"" FldSrchOpr2=>"" FldStrFunc=>"" FldSupport=>""1"" FldTitle=>"" FldType=>""135"" FldTypeName=>""TIMESTAMP"" FldUniqueIdx=>""0"" FldUploadPath=>"" FldUploadResize=>""0"" FldUseDHTMLEditor=>""0"" FldUseParen=>""-2"" FldValidate=>""EURODATE"" FldView=>""0"" FldViewCustomAttributes=>"" FldViewTag=>""FORMATTED TEXT"" FldViewThumbnail=>""0"" FldZeroLen=>""1"" FileNameFld=>"" FileSizeFld=>"" FileTypeFld=>"" ImageHeightFld=>"" ImageWidthFld=>"" NativeDataType=>""7"""; RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase; 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