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

/
/
i

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/\s+TStatusBar/i'; $str = 'inherited FormPadrao: TFormPadrao Left = 354 Top = 155 Caption = \'FormPadrao\' ClientHeight = 342 ClientWidth = 655 KeyPreview = True PopupMenu = MnPop_Principal OnCloseQuery = FormCloseQuery OnDeactivate = FormDeactivate ExplicitWidth = 671 ExplicitHeight = 381 DesignSize = ( 655 342) PixelsPerInch = 96 TextHeight = 15 object Bv_Top: TBevel [0] Left = 0 Top = 0 Width = 655 Height = 2 Align = alTop end object Sb_FormPadrao: TStatusBar [1] Left = 0 Top = 317 Width = 655 Height = 25 Panels = < item Bevel = pbNone Text = \'Usu\'#225\'rio\' Width = 100 end item Bevel = pbNone Width = 50 end> ParentColor = True ParentFont = True UseSystemFont = False ExplicitTop = 323 end object Pn_BaseToolBar: TPanel [2] Left = 0 Top = 2 Width = 655 Height = 73 Align = alTop BevelOuter = bvNone ParentColor = True TabOrder = 2 end object Pn_BaseGrid: TPanel [3] Left = 0 Top = 75 Width = 655 Height = 242 Align = alClient BevelOuter = bvNone BorderWidth = 3 ParentColor = True TabOrder = 4 ExplicitLeft = 32 ExplicitTop = 95 ExplicitHeight = 222 end inherited MinMax: TmgMinMax Top = 7 MinTrackSize.X = 450 MinTrackSize.Y = 300 ExplicitTop = 7 end object Mn_Principal: TMainMenu [6] Left = 4 Top = 36 object miTabela: TMenuItem Caption = \'&Tabela\' object miInserir: TMenuItem Caption = \'&Inserir\' end object miApagar: TMenuItem Caption = \'&Apagar\' end object miPropriedades: TMenuItem Caption = \'&Editar\' end object N4: TMenuItem Caption = \'-\' end object miFechar: TMenuItem Caption = \'&Fechar\' OnClick = miFecharClick end end object miEditar1: TMenuItem Caption = \'&Editar\' object miRecortar1: TMenuItem Caption = \'&Recortar\' end object miCopiar1: TMenuItem Caption = \'&Copiar\' end object miColar1: TMenuItem Caption = \'&Colar\' end end object miExibir: TMenuItem Caption = \'&Exibir\' object miBarradeFerramentas: TMenuItem Caption = \'Barra de &Ferramentas\' object miNaoExibir: TMenuItem Caption = \'&N\'#227\'o Exibir\' GroupIndex = 1 RadioItem = True OnClick = mi_NaoExibirClick end object N5: TMenuItem Caption = \'-\' GroupIndex = 1 RadioItem = True end object miAlto: TMenuItem Caption = \'&Alto\' GroupIndex = 1 RadioItem = True OnClick = mi_AltoClick end object miBaixo: TMenuItem Caption = \'&Baixo\' GroupIndex = 1 RadioItem = True OnClick = mi_BaixoClick end end object miBarradeStatus: TMenuItem Caption = \'Barra de &Status\' OnClick = mi_BarradeStatusClick end object mi_SepN3: TMenuItem Caption = \'-\' end object mi_Informacoesdajanela1: TMenuItem Caption = \'Informa\'#231#245\'es desta Janela\' OnClick = mi_Informacoesdajanela1Click end object mi_Sepm9: TMenuItem Caption = \'-\' Visible = False end object mi_OcorrenciaAuditoria: TMenuItem Caption = \'Logs de Auditoria\' Visible = False OnClick = mi_OcorrenciaAuditoriaClick end end object Mi_Ajuda: TMenuItem Caption = \'&Ajuda\' object Mi_AjudaProcesso: TMenuItem Caption = \'Ajuda &Processo\' ShortCut = 112 OnClick = Mi_AjudaProcessoClick end object Mi_AjudaTela: TMenuItem Caption = \'Ajuda &Tela\' ShortCut = 16496 OnClick = Mi_AjudaTelaClick end object Mi_HistoricoAlteracoes: TMenuItem Caption = \'&Hist\'#243\'rico de altera\'#231#245\'es\' Visible = False OnClick = Mi_HistoricoAlteracoesClick end end end inherited mgPopupImpressao: TmgPopupMenu Left = 4 end object MnPop_Principal: TPopupMenu Left = 34 Top = 36 object mi_Inserir: TMenuItem Caption = \'&Inserir\' end object mi_Apagar: TMenuItem Caption = \'&Apagar\' end object mi_Editar: TMenuItem Caption = \'&Editar\' end object N1: TMenuItem Caption = \'-\' end object mi_BarradeFerramentas: TMenuItem Caption = \'&Barra de Ferramentas\' object mi_NaoExibir: TMenuItem Caption = \'&N\'#227\'o Exibir\' GroupIndex = 1 RadioItem = True OnClick = mi_NaoExibirClick end object N2: TMenuItem Caption = \'-\' GroupIndex = 1 RadioItem = True end object mi_Alto: TMenuItem Caption = \'&Alto\' GroupIndex = 1 RadioItem = True OnClick = mi_AltoClick end object mi_Baixo: TMenuItem Caption = \'&Baixo\' GroupIndex = 1 RadioItem = True OnClick = mi_BaixoClick end end object mi_BarradeStatus: TMenuItem Caption = \'Ba&rra de Status\' OnClick = mi_BarradeStatusClick end end end'; $subst = " TMgStatusBar"; $result = preg_replace($re, $subst, $str, 1); echo "The result of the substitution is ".$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