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

/
/
s

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"desc\s*""(((?!"").)*)((?!\n).)*\n{1}task\s*:(((?!\n).)*)do(((?!\nend).)*)\nend"; string input = @"import 'cloud2/cloud2.rb' desc ""transfer db from current location to local and new dev"" task :fulldbtransfer => [ :dbdown, :dbup, :dbup_live,] $comps_db = ['prube_yalecomps'] $tnew_dbs = [ 'prube_yaletnew_drama_prod', 'prube_yaletnew_summer_cabaret_prod', 'prube_yaletnew_cabaret_prod', 'prube_yaletnew_music_prod', 'prube_yaletnew_rep_prod'] $new_tnew_dbs = [ 'prube_yaletnew_drama', 'prube_yaletnew_summer_cabaret', 'prube_yaletnew_cabaret', 'prube_yaletnew_music', 'prube_yaletnew_rep'] all_erube_dbs = $comps_db + $tnew_dbs desc ""Transfer Database, complete with tunnel setup and teardown"" task :dbdown do all_erube_dbs.each do |database_name| cloud2_mysqldump do tunnel_host 'cumulus-www-master-pub.rs.lynch2.com' tunnel_user 'www' db_host 'cumulus-db-master.rs.lynch2.com' skip_secure_auth true db_user 'mysql' db_pass 'mysql' db_name "" file_prefix 'SOURCE_' ignored_tables ['cache','hits','debug','sessionvars','sessions'] end end end task :dbsandr do dbname = ""prube_yalecomps"" bucket_prefix = ""comps"" cloud2_sed do source_file ""db-tools/SOURCE_mysqldump_ dest_file ""db-tools/CLOUD2_ find_str [ ] replace_str [ ] end dbname = ""prube_yaletnew_drama_prod"" bucket_prefix = ""drame"" cloud2_sed do source_file ""db-tools/SOURCE_mysqldump_ dest_file ""db-tools/CLOUD2_ find_str [ 'prube_yaletnew_drama_prod', ] replace_str [ ""prube_yaletnew_drama"", ] end dbname = ""prube_yaletnew_summer_cabaret_prod"" bucket_prefix = ""summer-cabaret"" cloud2_sed do source_file ""db-tools/SOURCE_mysqldump_ dest_file ""db-tools/CLOUD2_ find_str [ 'prube_yaletnew_summer_cabaret_prod', ] replace_str [ 'prube_yaletnew_summer_cabaret', ] end dbname = ""prube_yaletnew_cabaret_prod"" bucket_prefix = ""cabaret"" cloud2_sed do source_file ""db-tools/SOURCE_mysqldump_ dest_file ""db-tools/CLOUD2_ find_str [ 'prube_yaletnew_cabaret_prod', ] replace_str [ 'prube_yaletnew_cabaret', ] end dbname = ""prube_yaletnew_music_prod"" bucket_prefix = ""music"" cloud2_sed do source_file ""db-tools/SOURCE_mysqldump_ dest_file ""db-tools/CLOUD2_ find_str [ 'prube_yaletnew_music_prod', ] replace_str [ 'prube_yaletnew_music', ] end dbname = ""prube_yaletnew_rep_prod"" bucket_prefix = ""rep"" cloud2_sed do source_file ""db-tools/SOURCE_mysqldump_ dest_file ""db-tools/CLOUD2_ find_str [ 'prube_yaletnew_rep_prod', ] replace_str [ 'prube_yaletnew_rep', ] end end desc ""Send Database to tigard-dev-rds"" task :dbup do upload_dbs ""reston-dev-rds.aws.lynch2.com"" end desc ""Send Database to tigard-mail2-rds"" task :dbup_live do upload_dbs ""reston-live-rds.aws.lynch2.com"" end def upload_dbs (dbhost) $comps_db.each do |database_name| cloud2_mysql do db_host dbhost db_user 'mysql' db_pass 'mysql' db_name ""mysql"" sql_files [""CLOUD2_ end cloud2_mysql do db_host dbhost db_user 'mysql' db_pass 'mysql' db_name "" sql_files [""erube_upgrade.sql""] end end $new_tnew_dbs.each do |database_name| cloud2_mysql do db_host dbhost db_user 'mysql' db_pass 'mysql' db_name ""mysql"" sql_files [""CLOUD2_ end cloud2_mysql do db_host dbhost db_user 'mysql' db_pass 'mysql' db_name "" sql_files [""tnew_erube_upgrade.sql""] end end end "; RegexOptions options = RegexOptions.Singleline; Match m = Regex.Match(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