Create list or arrays in Windows Batch

Question

Can I declare a list or array in a batch file like this:

set list = "A B C D" 

And then I need to write these to a file, with the spaces between:

A  B  C   D 

Answer 1

Yes, you may use both ways. If you just want to separate the elements and show they in separated lines, a list is simpler:

set list=A B C D 

A list of values separated by space may be easily processed by for command:

(for %%a in (%list%) do (    echo %%a    echo/ )) > theFile.txt 

You may also create an array this way:

setlocal EnableDelayedExpansion set n=0 for %%a in (A B C D) do (    set vector[!n!]=%%a    set /A n+=1 ) 

and show the array elements this way:

(for /L %%i in (0,1,3) do (    echo !vector[%%i]!    echo/ )) > theFile.txt 

For further details about array management in Batch files, see: Arrays, linked lists and other data structures in cmd.exe (batch) script

ATTENTION! You must know that all characters included in set command are inserted in the variable name (at left of equal sign), or in the variable value. For example, this command:

set list = "A B C D" 

create a variable called list (list-space) with the value "A B C D" (space, quote, A, etc). For this reason, it is a good idea to never insert spaces in set commands. If you need to enclose the value in quotes, you must enclose both the variable name and its value:

set "list=A B C D" 

PS - You should NOT use ECHO. in order to left blank lines! An alternative is ECHO/. For further details about this point, see: http://www.dostips.com/forum/viewtopic.php?f=3&t=774