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"
"
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^(?P<unit_type>S)(?P<unit_size>6|8|10|15|20|25|30)(?P<mounting_type>A|P)(?P<cracking_pressure>00|02|05|15|30|50|80)(?P<sep_1>-)(?P<unit_series>1X)(?P<sep_2>/|=)(?P<pressure_rating_max>420|450|)(?P<surface_coating>J3|J5|V|)(?P<orifice_position>B|)(?P<orifice_diameter>00|03|05|08|10|12|15|)(?P<pipe_port>/2|/12|)(?P<special_version>(.|[0-9])*)$"; string input = @"S20P15-1X/ S30P05-1X/V S30P02-1X/V S30P15-1X/V S30P30-1X/V S30P50-1X/V S30P00-1X/ S30P05-1X/ S30P15-1X/ S30P30-1X/ S30P50-1X/ S10P00-1X/ S10P05-1X/ S10P05-1X/V S10P15-1X/ S10P15-1X/V S10P30-1X/ S10P30-1X/V S10P50-1X/ S20P00-1X/ S20P05-1X/ S20P05-1X/SO74 S20P05-1X/V S20P05-1X/VSO74 S20P15-1X/SO74 S20P15-1X/V S20P30-1X/ S20P30-1X/SO74 S20P30-1X/V S20P30-1X/VSO74 S20P50-1X/ S30P05-1X/VSO74 S30P00-1X/SO74 S30P15-1X/SO74 S30P05-1X/SO74 S25P15-1X/V S15P15-1X/V S15P15-1X/ S25P15-1X/ S10A05-1X/450J3 S20A05-1X/450J3 S30P05-1X=V S30P50-1X=V S10P05-1X=V S10P30-1X=V S20P05-1X=V S15A02-1X/450J3 S20A02-1X/450J3 S10A05-1X/450J3/12 S20A05-1X/450J3B15/12 S10A15-1X/450J3/12 S20A30-1X/450J3 S6A00-1X/450J3 S6A02-1X/450J3 S6A05-1X/450J3 S6A15-1X/450J3 S6A30-1X/450J3 S6A50-1X/450J3 S8A00-1X/450J3 S8A02-1X/450J3 S8A05-1X/450J3 S8A15-1X/450J3 S8A30-1X/450J3 S8A50-1X/450J3 S10A00-1X/450J3 S10A02-1X/450J3 S10A02-1X/450J3/12 S10A15-1X/450J3 S10A30-1X/450J3 S10A50-1X/450J3 S15A00-1X/450J3 S15A05-1X/450J3B00 S15A05-1X/450J3 S15A15-1X/450J3 S15A30-1X/450J3 S15A50-1X/450J3 S20A00-1X/450J3 S20A02-1X/450J3/12 S20A05-1X/450J3/12 S20A15-1X/450J3 S20A30-1X/450J3/12 S20A50-1X/450J3 S25A00-1X/420J3 S25A02-1X/420J3 S25A05-1X/420J3 S25A15-1X/420J3 S25A30-1X/420J3 S25A50-1X/420J3 S25A80-1X/420J3 S30A00-1X/420J3 S30A02-1X/420J3 S30A05-1X/420J3 S30A15-1X/420J3 S30A30-1X/420J3 S30A50-1X/420J3 S30A80-1X/420J3 S8A00-1X/450J3/12 S8A05-1X/450J3/12 S8A15-1X/450J3/12 S8A30-1X/450J3/12 S10A00-1X/450J3/12 S10A30-1X/450J3/12 S10A50-1X/450J3/12 S15A00-1X/450J3/12 S15A02-1X/450J3/12 S15A05-1X/450J3/12 S15A15-1X/450J3/12 S15A30-1X/450J3/12 S15A50-1X/450J3/12 S20A00-1X/450J3/12 S20A15-1X/450J3/12 S20A50-1X/450J3/12 S25A00-1X/420J3/12 S25A02-1X/420J3/12 S25A05-1X/420J3/12 S25A15-1X/420J3/12 S25A30-1X/420J3/12 S25A50-1X/420J3/12 S30A00-1X/420J3/12 S30A02-1X/420J3/12 S30A05-1X/420J3/12 S30A15-1X/420J3/12 S30A30-1X/420J3/12 S30A50-1X/420J3/12 S10A05-1X/450J3B08 S10A05-1X/450J3B15 S25A15-1X/420J3B10 S25A50-1X/420J3B00 S10A05-1X/450J3B00 S20A05-1X/450J3B00 S30A05-1X/420J3B00 S30A05-1X/420J3B10 S30A80-1X/420J3B12 S15A05-1X/450J5/12 S8A05-1X/450J3B03 S30A50-1X/420J3B12 S10A05-1X/450J3B10 S30A30-1X/420J3B12 S25A30-1X/420J3B12 S15A05-1X/450J5 S15A05-1X/450J5/12=AH S8A05-1X/450J3B08 S10A05-1X=450J3 S25A00-1X/420J3B10 S10A05-1X/450J3B12 S30A05-1X=420J3 S10A50-1X/450J3/2 S8A05-1X/450J3B05 S15A50-1X/450J5 S10A05-1X/450J3B10/12 S25A50-1X/420J3B10 S15A05-1X/450J3/2 S15A05-1X/450J3B10 S20A05-1X/450J3B10 S25A05-1X=420J3/12 S8A50-1X/450J5 S8A05-1X/450J3B00 S15A05-1X=450J3 S25A05-1X=420J3 S20A05-1X/450J3B15 S6A05-1X=450J3 S15A30-1X/450J3B10 S20A05-1X/450J5 S20A30-1X/450J3B15 "; RegexOptions options = RegexOptions.Multiline; 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