CODEWITHSUNDEEP
variablesbatch-fileextract
BLS
BLS

Reputation: 5

Batchfile - extract path from file contents into cmd variable

I'm hoping someone may be able to help.

Dropbox stores its path in a file called 'info.json'. The contents of my file is as follows:

{"personal": {"path": "C:\\Users\\Sam\\Dropbox", "host": 241656592}}

{"business": {"path": "C:\\Common\\Allusers\\Dropbox", "host": 45143292}}

I need to extract the 'personal' path only to a Windows CMD variable %dropboxpath% using only a windows batch script. I have tried using FOR and FINDSTR but couldn't make it work.

The other issue is stripping away the extra backslashes in the path to leave 'C:\Users\Sam\Dropbox'.

I believe FINDSTR should locate the 'personal' line and FOR should extract everything after "path": but before , "host" and then somehow, remove the double backslashes.

Hope this makes sense and really appreciate any help you could give.

Many thanks, Sam

Upvotes: 0

Views: 246

Answers (3)

MichaelS
MichaelS

Reputation: 6042

As you need to modify and evaluate your variables at run time and not at parse time, you will need to use EnableDelayedExpansion and !...! instead of %...%. However, this code will work if the two lines you've posted are correct.

@ECHO OFF
SETLOCAL EnableDelayedExpansion
FOR /F "tokens=*" %%a IN (scanword.txt) DO (
    SET line=%%a
    IF "!line:~2,8!"=="personal" SET dropboxpath=%%a
)
FOR /F "tokens=3" %%a IN ("!dropboxpath!") DO (
    SET dropboxpath=%%a
)
SET dropboxpath=!dropboxpath:"=!
SET dropboxpath=!dropboxpath:,=!
SET dropboxpath=!dropboxpath:\\=\!
ECHO !dropboxpath!
PAUSE

The path will be stored in !dropboxpath! and not in %dropboxpath% as you requested but I hope that's ok ;-)

Upvotes: 0

MC ND
MC ND

Reputation: 70933

@echo off
    setlocal enableextensions disabledelayedexpansion

    set "file=info.json"

    for /f usebackq^ tokens^=2^,6^ delims^=^" %%a in ("%file%") do (
        if /i "%%a"=="personal" set "dropboxpath=%%~fb"
    )
    echo %dropboxpath%

Using the quotes as delimiters, split the line, so delimiters and tokens are

{"personal": {"path": "C:\\Users\\Sam\\Dropbox", "host": 241656592}}    
 ^        ^   ^    ^  ^                       ^  ^    ^
1 2        3   4    5  6                       7  8    9

we request the fourth and sixth tokens into %%a and %%b and if %%a is personal, then %%b is the path

Or, you can try with 

@echo off
    setlocal enableextensions disabledelayedexpansion

    set "file=info.json"

    for /f "delims=" %%a in ('findstr /l /i /c:"{\"personal\"" "%file%"'
    ) do for %%b in (%%a
    ) do for /f "tokens=4 delims=\:" %%c in ("%%~b"
    ) do set "dropboxpath=%%~fb"

    echo %dropboxpath%
  • findstr is used to find the required line in the input file. This line retrieved by ...
  • for /f %%a who called the findstr command. For each retrieved line ...
  • for %%b will iterate over the elements in the line stored in %%a and for each ...
  • for /f %%c will split the element using colon and backslash as delimiters and trying to find the fouth token. As the only element in the line with four tokens is the path...
  • we set the variable to the full path of the element

Upvotes: 1

Magoo
Magoo

Reputation: 80033

@ECHO OFF
SETLOCAL
FOR /f "tokens=1,3*delims={:" %%a IN (q29817666.txt) DO IF /i "%%~a"=="personal" (
 FOR %%p IN (%%c) DO SET "dropboxpath=%%~p"&GOTO process
)
:process
SET "dropboxpath=%dropboxpath:\\=\%"
ECHO dropboxpath=%dropboxpath%

GOTO :EOF

I used a file named q29817666.txt containing your data for my testing.

The tokens/delimiters combination selects "personal" to %%a, a space to%%band "C:\Users\Sam\Dropbox", "host": 241656592}}to%%c`

if %%a (stripped of enclosing quotes) is equal to the string personal. %%c is then processed as a series of elements separated by spaces and commas. Since the first element is of interest and it's quoted, then %%p will acquire "C:\\Users\\Sam\\Dropbox" and this, stripped of enclosing quotes will be assigned to the variable dropbox and the loop is then terminated by the goto.

Then replace double-backslashes with single. Done.

Upvotes: 1

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