Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

/
/
ig

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\b(FLOWLINKMEDIA ID=)"; string input = @"<FLOWLINKMEDIA ID=""LDP_COMPLETE""> <PART NAME=""MAIN""> <GRPH ZORDER=""0"" W=""4000"" H=""3000""> <SOURCE>back01.png</SOURCE> </GRPH> <GRPH ZORDER=""1"" TP=""#00FF00""> <SOURCE LOCATION=""VAR"">MKTAD:MAIN_TILE</SOURCE> </GRPH> </PART> <PART NAME=""OMP""> <REGION NAME=""REQUEST_BOTTOM""> <TEXTBOX STYLE=""REQUEST_PROMPT""> <SOURCE LOCATION=""VAR"">LANG:INF_ONEMOMENT</SOURCE> </TEXTBOX> </REGION> </PART> </FLOWLINKMEDIA> <FLOWLINKMEDIA ID=""LDP_DEPOSITMENU""> <SM NAME=""SMDL"" /> <PART NAME=""MAIN""> <GRPH ZORDER=""0"" W=""4000"" H=""3000""> <SOURCE>back01.png</SOURCE> </GRPH> <REGION NAME=""MARKETING_BANNER""> <GRPH ZORDER=""1"" TP=""#00FF00""> <SOURCE LOCATION=""VAR"">MKTAD:OPENER_TILE</SOURCE> </GRPH> </REGION> <REGION NAME=""MAIN""> <TEXTBOX STYLE=""LINE1_LARGEPROMPT_WIDE""> <SOURCE LOCATION=""VAR"">LANG:PRM_INT_LDPMENU</SOURCE> </TEXTBOX> <SPEECH SCR_COMP=""PROMPT""> <SOURCE LOCATION=""VAR"">LANG:TTS_PAUSE</SOURCE> </SPEECH> <TEXTBOX STYLE=""PROMPT_SUBTEXT""> <VARSOURCE> <SOURCE LOCATION=""VAR"">LANG:INF_BCREFERENCE</SOURCE> <VAR NAME=""BCTOACCT""> <SOURCE LOCATION=""VAR"">BUSOBJ:USERDATA\TOACCT\NAME_NUMBER</SOURCE> </VAR> </VARSOURCE> </TEXTBOX> <SPEECH SCR_COMP=""PROMPT""> <SOURCE LOCATION=""VAR"">LANG:TTS_PAUSE</SOURCE> </SPEECH> </REGION> </PART> <PART NAME=""NAV_BAR""> <REGION NAME=""NAVIGATION_BAR""> <GRPH ZORDER=""1"" TP=""#00FF00""> <SOURCE>nav_bar.png</SOURCE> </GRPH> </REGION> </PART> <PART NAME=""CANCEL""> <ACTIONKEY VALUE=""CANCEL""/> <REGION NAME=""NAVIGATION_BAR_LEFT_BTN"" TOUCH=""Y""> <GRPH ZORDER=""2"" Y=""80"" X=""90""> <SOURCE>nav_exit.png</SOURCE> </GRPH> <TEXTBOX STYLE=""NAVBAR_LEFT_OPTION""> <SOURCE LOCATION=""VAR"">LANG:FDK_CANCEL</SOURCE> </TEXTBOX> </REGION> </PART> <PART NAME=""TYPE_PANEL""> <REGION NAME=""MAIN_PANEL"" TOUCH=""N""> <GRPH ZORDER=""1""> <SOURCE>main_panel.png</SOURCE> </GRPH> </REGION> </PART> <DISPLAYLIST LISTNAME=""DEPTYPE"" EVENTNAME=""FE_SELECTED""> <POSITIONS> <POS REGION_NAME=""MAIN_PANEL_1OF3"" TOUCH=""Y""> <SPITEM ITEMNAME=""SHOW"" ENABLEINPUT=""Y""> <GRPH ZORDER=""3""> <SOURCE>primary_tile_1.png</SOURCE> </GRPH> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER""> <VARSOURCE LOCATION=""VAR""> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=""DISPLAYLIST"">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=""GHOST"" ENABLEINPUT=""N""> <GRPH ZORDER=""1"" TP=""#00FF00""> <SOURCE>primary_tile_1_ghost.png</SOURCE> </GRPH> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER_1OF2""> <VARSOURCE LOCATION=""VAR""> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=""DISPLAYLIST"">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER_2OF2""> <SOURCE LOCATION=""VAR"">LANG:MENU_TEMP_UNAVAILABLE</SOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=""HIDE"" ENABLEINPUT=""N""/> <RESPONSE DISPLAYTIME=""100""> <GRPH ZORDER=""0"" TP=""#00FF00""> <SOURCE>Highlight\primary_tile_1.png</SOURCE> </GRPH> </RESPONSE> </POS> <POS REGION_NAME=""MAIN_PANEL_2OF3"" TOUCH=""Y""> <SPITEM ITEMNAME=""SHOW"" ENABLEINPUT=""Y""> <GRPH ZORDER=""3""> <SOURCE>primary_tile_1.png</SOURCE> </GRPH> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER""> <VARSOURCE LOCATION=""VAR""> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=""DISPLAYLIST"">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=""GHOST"" ENABLEINPUT=""N""> <GRPH ZORDER=""1"" TP=""#00FF00""> <SOURCE>primary_tile_1_ghost.png</SOURCE> </GRPH> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER_1OF2""> <VARSOURCE LOCATION=""VAR""> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=""DISPLAYLIST"">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER_2OF2""> <SOURCE LOCATION=""VAR"">LANG:MENU_TEMP_UNAVAILABLE</SOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=""HIDE"" ENABLEINPUT=""N""/> <RESPONSE DISPLAYTIME=""100""> <GRPH ZORDER=""0"" TP=""#00FF00""> <SOURCE>Highlight\primary_tile_1.png</SOURCE> </GRPH> </RESPONSE> </POS> <POS REGION_NAME=""MAIN_PANEL_3OF3"" TOUCH=""Y""> <SPITEM ITEMNAME=""SHOW"" ENABLEINPUT=""Y""> <GRPH ZORDER=""3""> <SOURCE>primary_tile_1.png</SOURCE> </GRPH> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER""> <VARSOURCE LOCATION=""VAR""> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=""DISPLAYLIST"">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=""GHOST"" ENABLEINPUT=""N""> <GRPH ZORDER=""1"" TP=""#00FF00""> <SOURCE>primary_tile_1_ghost.png</SOURCE> </GRPH> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER_1OF2""> <VARSOURCE LOCATION=""VAR""> <SOURCE>LANG:INF_LDPMENU_</SOURCE> <SOURCE LOCATION=""DISPLAYLIST"">VALUE</SOURCE> </VARSOURCE> </TEXTBOX> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER_2OF2""> <SOURCE LOCATION=""VAR"">LANG:MENU_TEMP_UNAVAILABLE</SOURCE> </TEXTBOX> </SPITEM> <SPITEM ITEMNAME=""HIDE"" ENABLEINPUT=""N""/> <RESPONSE DISPLAYTIME=""100""> <GRPH ZORDER=""0"" TP=""#00FF00""> <SOURCE>Highlight\primary_tile_1.png</SOURCE> </GRPH> </RESPONSE> </POS> </POSITIONS> <SMDEFINED> <SMITEM SMNAME=""MORE"" EVENTNAME=""MORE""> <GRPH ZORDER=""1"" TP=""#00FF00""> <SOURCE>primary_tile_1.png</SOURCE> </GRPH> <TEXTBOX STYLE=""PRIMARY_TILE1_CENTER""> <SOURCE LOCATION=""VAR"">LANG:FDK_MOREACCTS</SOURCE> </TEXTBOX> </SMITEM> </SMDEFINED> </DISPLAYLIST> </FLOWLINKMEDIA>"; RegexOptions options = RegexOptions.IgnoreCase; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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