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Batch file to comment specific lines into a text file

Posted on 2012-12-26
Medium Priority
Last Modified: 2012-12-28
Hi Experts,

Happy cristmas for all, and hope we find all the happiness, health and money (lotof money $$$)  :D

Please, i need to do a batch file like that :

MyBatchFile.bat    file.txt    FileWithLineToComment.txt

Where :

     it's a text file, this one containall the lines text (not numbers of line) that we need to comment.

   Containe all the lines

   Is the program that i need to write. This batch file will :
  1- open FileWithLineToComment.txt, and read line by line
  2- for each line we read, we will search it into the "MyFile.txt"
  3- one time we find it we will add " // " in the first of the find line, and like that it will be

Exemple :

MyFile.txt Containe :

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if i do this command line :
MyBatchFile.bat    file.txt    FileWithLineToComment.txt

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MyFile.txt   will be like that:

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Hope you can help me

Question by:Joesephlebon
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LVL 43

Expert Comment

by:Steve Knight
ID: 38723048
Are these real world examples, or are they going to be text files with any amount of data, words, spaces, commas, other characters potentially on the line.  Same for the list of lines to check?

Are there any blank lines etc. in the file that are important?

And just to check it seems you are checking the whole line to comment, i.e. if your string was found part way across the line.

If all of those end up being just like your answer it is a relatively simple for loop but no point writing that if not.


LVL 57

Accepted Solution

Bill Prew earned 2000 total points
ID: 38727187
This should give you a pretty good place to start, let me know what questions you have.

@echo off
setlocal EnableDelayedExpansion

REM Make sure required parms were supplied
if "%~1" EQU "" (
  echo No data file specified to process
  exit /b
if "%~2" EQU "" (
  echo No comment file specified to process
  exit /b

REM Get input file and comment file from command line parms
set Filename=%~1
set Comments=%~2

REM Define name for temporary file
set Outfile=%Temp%\%~nx1

REM Send changed file to tem file for now
  REM Read each line of file
  for /F "usebackq tokens=*" %%L in ("%Filename%") do (
    REM Read each line from comment file
    set MakeComment=N
    for /F "usebackq tokens=*" %%C in ("%Comments%") do (
      REM If this line is to be commented flag it

      if /I "%%L" EQU "%%C" set MakeComment=Y
    if "!MakeComment!" EQU "Y" (
    ) else (

if exist "%Outfile%" (
  copy /Y "%Outfile%" "%Filename%" >NUL
  del "%Outfile%" >NUL

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Author Closing Comment

ID: 38728037
Thanks so much Experts ;)
It's work fine :)
LVL 57

Expert Comment

by:Bill Prew
ID: 38728305
Welcome, glad that was useful.


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