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

/
/
gms

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?ms)(?<text>N?'((?:''|[^'])*)'|N?"((?:""|[^"])*)")" Local $sString = "USE [master]" & @CRLF & _ "GO" & @CRLF & _ "" & @CRLF & _ "IF OBJECT_ID('dbo.sp_foreach_db') IS NOT NULL" & @CRLF & _ " DROP PROCEDURE [dbo].[sp_foreach_db] " & @CRLF & _ "GO" & @CRLF & _ "" & @CRLF & _ "CREATE PROCEDURE [dbo].[sp_foreach_db] " & @CRLF & _ "(" & @CRLF & _ " @tsql NVARCHAR(MAX) = NULL" & @CRLF & _ " ,@replacedatabasenamepattern NVARCHAR(20) = N'?'" & @CRLF & _ "" & @CRLF & _ " ,@break_on_error BIT = 1" & @CRLF & _ "" & @CRLF & _ " ,@db_name_like NVARCHAR(128) = NULL" & @CRLF & _ " ,@db_name_in NVARCHAR(4000) = NULL" & @CRLF & _ " ,@db_name_not_in NVARCHAR(4000) = NULL" & @CRLF & _ " ,@db_use_system_db BIT = 0" & @CRLF & _ " ,@db_use_temp_db BIT = 0" & @CRLF & _ "" & @CRLF & _ " ,@push_info_msg BIT = 1" & @CRLF & _ ")" & @CRLF & _ "WITH EXECUTE AS CALLER " & @CRLF & _ "AS" & @CRLF & _ "/*" & @CRLF & _ "Version: 1.0.1.0" & @CRLF & _ "Developer: Paw Jershauge" & @CRLF & _ "Created: 18-03-2016 13:01:00" & @CRLF & _ "*/" & @CRLF & _ "BEGIN" & @CRLF & _ " IF @tsql IS NULL" & @CRLF & _ " RETURN 0;" & @CRLF & _ " " & @CRLF & _ " SET NOCOUNT ON;" & @CRLF & _ " DECLARE @dbtsql NVARCHAR(MAX)" & @CRLF & _ " ,@firecode NVARCHAR(MAX)" & @CRLF & _ " ,@db_name NVARCHAR(128)" & @CRLF & _ " ,@dbnames NVARCHAR(MAX) = N''" & @CRLF & _ " ,@has_replacement BIT = 0" & @CRLF & _ " ,@msg_str NVARCHAR(2044)" & @CRLF & _ "" & @CRLF & _ " SET @dbtsql = N'SELECT @dbnames += [name] + CHAR(10) FROM [master].[sys].[databases] WHERE [state] = 0'" & @CRLF & _ " SET @dbtsql += IIF(ISNULL(@db_use_temp_db, 0) = 1, N'', N' AND [database_id] <> 2')" & @CRLF & _ " SET @dbtsql += IIF(ISNULL(@db_use_system_db, 0) = 1, N'', N' AND [database_id] > 4')" & @CRLF & _ " SET @dbtsql += IIF(NULLIF(@db_name_like, N'') IS NULL, N'', N' AND [name] LIKE ''' + @db_name_like + N'''')" & @CRLF & _ " SET @dbtsql += IIF(NULLIF(@db_name_in, N'') IS NULL, N'', N' AND [name] IN (' + @db_name_in + N')')" & @CRLF & _ " SET @dbtsql += IIF(NULLIF(@db_name_not_in, N'') IS NULL, N'', N' AND [name] NOT IN (' + @db_name_not_in + N')')" & @CRLF & _ " " & @CRLF & _ " EXEC sp_executesql @dbtsql, N'@dbnames NVARCHAR(MAX) OUTPUT', @dbnames = @dbnames OUTPUT;" & @CRLF & _ "" & @CRLF & _ " SELECT @has_replacement = CAST(CHARINDEX(ISNULL(@replacedatabasenamepattern, N'?'), @tsql) AS BIT)" & @CRLF & _ " " & @CRLF & _ " DECLARE cur_db CURSOR LOCAL FORWARD_ONLY FAST_FORWARD READ_ONLY FOR SELECT [value] FROM STRING_SPLIT(@dbnames, CHAR(10)) WHERE [value] <> N'' ORDER BY [value]" & @CRLF & _ " OPEN cur_db" & @CRLF & _ " FETCH NEXT FROM cur_db INTO @db_name" & @CRLF & _ " WHILE @@FETCH_STATUS = 0 " & @CRLF & _ " BEGIN " & @CRLF & _ " BEGIN TRY" & @CRLF & _ " SELECT @firecode = N'EXEC (N''' + IIF(@has_replacement = 0,N'Use [' + @db_name + N']; ', N'') + REPLACE(REPLACE(@tsql, ISNULL(@replacedatabasenamepattern, N'?'), @db_name), N'''', N'''''') + N''')'" & @CRLF & _ " " & @CRLF & _ " IF @push_info_msg = 1" & @CRLF & _ " BEGIN" & @CRLF & _ " SET @msg_str = CONVERT(NVARCHAR(40),GETDATE(), 121) + N':Executing on ' + @db_name" & @CRLF & _ " RAISERROR (@msg_str, 0, 1) WITH NOWAIT" & @CRLF & _ " END" & @CRLF & _ " EXEC sp_executesql @firecode" & @CRLF & _ " IF @push_info_msg = 1" & @CRLF & _ " BEGIN" & @CRLF & _ " SET @msg_str = CONVERT(NVARCHAR(40),GETDATE(), 121) + N':' + @db_name + N' Done!'" & @CRLF & _ " RAISERROR (@msg_str, 0, 1) WITH NOWAIT" & @CRLF & _ " END" & @CRLF & _ " END TRY" & @CRLF & _ " BEGIN CATCH" & @CRLF & _ " SET @msg_str = 'Database ' + @db_name + ' failed with the following message:'" & @CRLF & _ " RAISERROR (@msg_str, 0, 1) WITH NOWAIT" & @CRLF & _ " SET @msg_str = ERROR_MESSAGE()" & @CRLF & _ " RAISERROR (@msg_str, 0, 1) WITH NOWAIT --Workaround of the PRINT Command that is stacked and released in reverse order, on remote servers" & @CRLF & _ "" & @CRLF & _ " IF @break_on_error = 1" & @CRLF & _ " THROW" & @CRLF & _ " END CATCH" & @CRLF & _ "" & @CRLF & _ " FETCH NEXT FROM cur_db INTO @db_name" & @CRLF & _ " END" & @CRLF & _ " CLOSE cur_db" & @CRLF & _ " DEALLOCATE cur_db" & @CRLF & _ "" & @CRLF & _ "END" & @CRLF & _ "GO" & @CRLF & _ "" & @CRLF & _ "EXEC sys.sp_MS_marksystemobject sp_foreach_db" & @CRLF & _ "GO" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm