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

r"
"
g

Test String

Substitution

Processing...

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?mi)((?:password=|user=)[^\n]*$|\<property key=\""variableNames\""\/\>\n|\<property key=\""variableValues\""\/\>\n)"; string substitution = @""; string input = @"<maplayer simplifyAlgorithm=""0"" minimumScale=""0"" maximumScale=""2500"" simplifyDrawingHints=""0"" readOnly=""0"" minLabelScale=""0"" maxLabelScale=""1e+08"" simplifyDrawingTol=""1"" geometry=""Point"" simplifyMaxScale=""1"" type=""vector"" hasScaleBasedVisibilityFlag=""1"" simplifyLocal=""1"" scaleBasedLabelVisibilityFlag=""0""> <id></id> <datasource>port=1521 user=test_user password=test_passwd</datasource> <keywordList> <value></value> </keywordList> <featformsuppress>0</featformsuppress> <editorlayout>generatedlayout</editorlayout> <widgets/> <conditionalstyles> <rowstyles/> <fieldstyles/> </conditionalstyles> </maplayer> </projectlayers> <properties> <Variables> <variableNames type=""QStringList""> <value>paswd</value> <value>user</value> </variableNames> <variableValues type=""QStringList""> <value>5zdgf</value> <value>dgdgdgfdg</value> </variableValues> </Variables> <customproperties> <property key=""labeling/textColorR"" value=""0""/> <property key=""labeling/textTransp"" value=""0""/> <property key=""labeling/upsidedownLabels"" value=""0""/> <property key=""labeling/useSubstitutions"" value=""false""/> <property key=""labeling/wrapChar"" value=""/> <property key=""labeling/xOffset"" value=""0""/> <property key=""labeling/yOffset"" value=""0""/> <property key=""labeling/zIndex"" value=""0""/> <property key=""variableNames""/> <property key=""variableValues""/> </customproperties>"; Regex regex = new Regex(pattern); 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