Windows – How to set to a variable, the result of a expression

batch filecommand linewindows

I need to extract the date of a file, then use this string as part of the name of a new file. I tried to solve this using the next commands:

First I get the details of the file and redirect the output to a temporary file.

DIR c:/myfolder/thefile.txt >> tmp.txt

Then I use FINDSTR to get the line that contains the date, if exist a way to get only the date I didn't found it:

FINDSTR [0-9]*\/[0-9]*\/[0-9] tmp.txt

The output is:

10/04/2012 07:55 66,029 thefile.txt

Now I want to set this result to a variable:

SET vartmp=FINDSTR [0-9]*\/[0-9]*\/[0-9] tmp.txt

It seems that it worked, because when i put %vartmp% returns the result:

10/04/2012 07:55 66,029 thefile.txt

But when I try to extract a part of vartmp, begin the problems:

ECHO %vartmp:~0,2%

It's returning me the string "FI" when I expected "10", seems that vartmp is saving the expression and not the result of the expression, I'm trying assign the result of the expression to an another tempvar, then extract a substring of tempvar but nothing has changed.

Best Answer

The FOR command can be used to chop up a line into tokens so you can grab just the part you want. With /f you can run it on the output of other commands, in this case the output of DIR filtered with FIND.

for /f "tokens=1" %%a in ('dir thefile.txt ^| Find "thefile.txt"') do (
set vartmp=%%a
)

Related Solutions

Windows – DOS Command Lines Move files to folders named with previous month

Your character selection requires that your date format looks like "MM-DD-YYYY". This command retrieves the number of the current month and subtracts one and saves it in a variable called prevmonth. It also subtracts one from the year if the previous month is December:

set /a prevmonth=%DATE:~0,2% - 1
set yearprevmo=%DATE:~6,4%
if %prevmonth% equ 0 set /a yearprevmo=%yearprevmo%-1 & set prevmonth=12
move -Y *.pdf "P:\CBO\Physician Monthly Reports\%yearprevmo%-%prevmonth%"

Note the quotes since there are spaces in your directory name.

Windows – BATCH Return string containing substring

Below is a good starting point using a batch script with a FOR loop simply echoing the path example as per your question and using batch variable substrings accordingly. You can easily replace the ECHO command within the loop with a DIR command to list the directories if that's what you need; just adjust the TOKEN number accordingly and test. You can replace the ECHO !str! with whatever other command(s) you need the script to process.

Batch Script 1

@ECHO ON
SETLOCAL ENABLEDELAYEDEXPANSION

FOR /F "TOKENS=2 DELIMS=\" %%F IN ('ECHO someOtherFolders\Project_Banana\05_Processing\05_Logs') DO (
    SET prjStr=%%~F 
    SET str=!prjStr:Project_=!
    ECHO !str! 
)

GOTO EOF

Result

Banana

Batch Script 2

@ECHO ON

SET SRC1=C:\Users
SET SRC2=Documents

FOR /D %%X IN ("%SRC1%\*") DO FOR /D %%Y IN ("%%X\%SRC2%\*") DO ECHO %%~Y
GOTO EOF

Potentially Helpful

@ECHO ON

::SETLOCAL ENABLEDELAYEDEXPANSION
SET DIR=C:\Users
FOR /F %%F IN ('DIR /B /AD "%DIR%"') DO (
    SET fldName=%%~F
    SET SRC1=C:\Users\%fldName%
    SET SRC2=Documents
FOR /D %%X IN ("%SRC1%") DO FOR /D %%Y IN ("%%X\%SRC2%\*") DO ECHO %%~FPY
)
GOTO EOF

Further Resources

Related Question