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

`
`
gmi

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?mi)((?<field>[a-z0-9]*)=>)(?<value>"[a-z0-9-_'/=> ]*")`) var str = `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"` var substitution = "'${field}' => ${value}," 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/