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
Processing...

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(""FILENAME"" ""([^\/:*?""<>|]+)"")"; string input = @"130 (UID 1245 BODYSTRUCTURE (((""TEXT"" ""PLAIN"" (""CHARSET"" ""UTF-8"") NIL NIL ""QUOTED-PRINTABLE"" 847 17 NIL NIL NIL)(""TEXT"" ""HTML"" (""CHARSET"" ""UTF-8"") NIL NIL ""QUOTED-PRINTABLE"" 2009 41 NIL NIL NIL) ""ALTERNATIVE"" (""BOUNDARY"" ""000000000000929e4505d59042b1"") NIL NIL)(""IMAGE"" ""JPEG"" (""NAME"" ""BS_01.jpg"") ""<f_kyetquhw1>"" NIL ""BASE64"" 280364 NIL (""ATTACHMENT"" (""FILENAME"" ""BS_(01)_a.jpg"")) NIL)(""IMAGE"" ""PNG"" (""NAME"" ""payroll_check_top_format.png"") ""<f_kyetquio3>"" NIL ""BASE64"" 498210 NIL (""ATTACHMENT"" (""FILENAME"" ""payroll check top format.png"")) NIL)(""IMAGE"" ""JPEG"" (""NAME"" ""missouri_dl_3e_1300x884.jpg"") ""<f_kyetquia2>"" NIL ""BASE64"" 1014040 NIL (""ATTACHMENT"" (""FILENAME"" ""missouri_dl_3e_1300x884.jpg"")) NIL)(""IMAGE"" ""JPEG"" (""NAME"" ""1040-1-1_N.jpg"") ""<f_kyetquhj0>"" NIL ""BASE64"" 4272596 NIL (""ATTACHMENT"" (""FILENAME"" ""1040-1-1_N.jpg"")) NIL) ""MIXED"" (""BOUNDARY"" ""000000000000929e4705d59042b3"") NIL NIL))"; 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