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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

`
`
img

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @` ""pack_id"": ""(.*)"" `; string input = @"I/okhttp.OkHttpClient: { ""route_state"": ""give_packs"", ""shelves"": [ { ""pack_id"": ""100142009300S2T1599432189"", ""shelf"": ""13"", ""total_goods"": 2, ""pack_state"": ""new"" }, { ""pack_id"": ""100143022336S5T1599502063"", ""shelf"": ""21"", ""total_goods"": 5, ""pack_state"": ""new"" }, { ""pack_id"": ""100143367911S2T1599558724"", ""shelf"": ""6"", ""total_goods"": 2, ""pack_state"": ""new"" }, { ""pack_id"": ""100143699532S5T1599568344"", ""shelf"": ""30"", ""total_goods"": 5, ""pack_state"": ""new"" }, { ""pack_id"": ""50127475503S1T1599567324"", ""shelf"": ""10"", ""total_goods"": 1, ""pack_state"": ""new"" }, { ""pack_id"": ""100143773834S4T1599570622"", ""shelf"": ""36"", ""total_goods"": 4, ""pack_state"": ""new"" }, { ""pack_id"": ""100143789121S1T1599571959"", ""shelf"": ""4"", ""total_goods"": 1, ""pack_state"": ""new"" }, { ""pack_id"": ""100143772313S1T1599587841"", ""shelf"": ""29"", ""total_goods"": 1, ""pack_state"": ""new"" }, { ""pack_id"": ""50127216356S2T1599555765"", ""shelf"": ""16"", ""total_goods"": 2, ""pack_state"": ""new"" }, { ""pack_id"": ""100143911917S9T1599578036"", ""shelf"": ""28"", ""total_goods"": 9, ""pack_state"": ""new"" }, { ""pack_id"": ""100144040317S3T1599592353"", ""shelf"": ""45"", ""total_goods"": 3, ""pack_state"": ""new"" }, { ""pack_id"": ""50122511688S10T1599216787"", ""shelf"": ""14"", ""total_goods"": 10, ""pack_state"": ""new"" }, { ""pack_id"": ""100143883877S3T1599580528"", ""shelf"": ""18"", ""total_goods"": 3, ""pack_state"": ""new"" }, { ""pack_id"": ""50125998587S5T1599460888"", ""shelf"": ""35"", ""total_goods"": 5, ""pack_state"": ""new"" }, { ""pack_id"": ""100143065694S7T1599505793"", ""shelf"": ""19"", ""total_goods"": 7, ""pack_state"": ""new"" }, { ""pack_id"": ""50126023780S18T1599462088"", ""shelf"": ""23"", ""total_goods"": 18, ""pack_state"": ""new"" }, { ""pack_id"": ""100143257387S1T1599516006"", ""shelf"": ""3"", ""total_goods"": 1, ""pack_state"": ""new"" }, { ""pack_id"": ""100143204003S8T1599513922"", ""shelf"": ""42"", ""total_goods"": 8, ""pack_state"": ""new"" }, { ""pack_id"": ""100143474921S10T1599546590"", ""shelf"": ""33"", ""total_goods"": 10, ""pack_state"": ""new"" }, { ""pack_id"": ""50126884830S5T1599522235"", ""shelf"": ""22"", ""total_goods"": 5, ""pack_state"": ""new"" }, { ""pack_id"": ""100142045579S1T1599431118"", ""shelf"": ""12"", ""total_goods"": 1, ""pack_state"": ""new"" } ] }"; RegexOptions options = RegexOptions.IgnoreCase | 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