How to read a string from a text file and use in a Windows batch file to extract a substring

We have a text file that we need containing the following sample. One constant string "D80" followed by another string:

D80KAAAAAA D80KBBBBBB D80KCCCCCC 

We want to extract it using a Windows batch script file (not powershell) and FOR loop to get this output:

AAAAAA BBBBBB CCCCCC 

So far we have gotten to this point. For illustration, i have shown the different attempts at extracting the substring:

setlocal EnableDelayedExpansion for /F "tokens=1 delims=" %%a in (TPLIST.txt) do ( echo %%a echo %%(a:~4,6) set substr1=%%(a:~4,6)% set substr2=%(a:~4,6)% set substr3=!(a:~4,6)! set substr4=%!(a:~4,6)!% echo %substr1% echo %substr2% echo %substr3% echo %substr4% ) 

However, the extract of the substring fails:

C:\User>setlocal EnableDelayedExpansion C:\User>for /F "tokens=1 delims=" %a in (TPLIST.txt) do ( echo %a echo %(a:~4,6 ) C:\User>( echo D80KAAAAAA echo %(a:~4,6 ) D80KAAAAAA %(a:~4,6 C:\User>( echo D80KBBBBBB echo %(a:~4,6 ) D80KBBBBBB %(a:~4,6 C:\User>( echo D80KCCCCCC echo %(a:~4,6 ) D80KCCCCCC %(a:~4,6 C:\User>set substr1=%(a:~4,6) C:\User>set substr2=~4,6) C:\User>set substr3=!(a:~4,6)! C:\User>set substr4=~4,6)! C:\User>echo %(a:~4,6) %(a:~4,6) C:\User>echo ~4,6) ~4,6) C:\User>echo ~4,6) ~4,6) C:\User>echo ~4,6) ~4,6) 

Any help would be greatly appreciated.

2 Answers

Howdo I extract a substring?

Your script is horribly broken so I rewrote it:

@echo off setlocal enabledelayedexpansion for /f "tokens=1,2,3" %%a in (test.txt) do ( set _s1=%%a set _s2=%%b set _s3=%%c echo !_s1:~4! echo !_s2:~4! echo !_s3:~4! ) endlocal 

Example usage:

F:\test>type test.txt D80KAAAAAA D80KBBBBBB D80KCCCCCC F:\test>test AAAAAA BBBBBB CCCCCC F:\test> 

Further Reading

• An A-Z Index of the Windows CMD command line | SS64.com
• Windows CMD Commands (categorized) - Windows CMD - SS64.com
• For /f - Loop through text - Windows CMD - SS64.com
• variable substring - Windows CMD - SS64.com

In Pure batch file you can do something like that :

@echo off Set "InputFile=TPLIST.txt" Set "OutPutFile=%~dp0Out-Extract.txt" setlocal enabledelayedexpansion > "%OutPutFile%" ( @for /f "delims=" %%a in ('Type "%InputFile%"') do ( set "_MyString=%%a" echo !_MyString:~4! ) ) endlocal If Exist "%OutPutFile%" Start "" "%OutPutFile%" 

In Powershell if another member wants to test using RegEx:

cls $MyString = @' D80KAAAAAA D80KBBBBBB D80KCCCCCC D80KDDDDDD D80KEEEEEE D80KFFFFFF D80KXXXXXX D80KYYYYYY D80KZZZZZZ '@ -split [System.Environment]::NewLine $pattern = '(?![D80K]).+' $MyString | %{ [regex]::matches($_,$pattern) } | %{ $_.Groups[0].Value } 

You will get as output for both solutions batch or powershell like that :

AAAAAA BBBBBB CCCCCC DDDDDD EEEEEE FFFFFF XXXXXX YYYYYY ZZZZZZ