Question

I have never done any batch scripting before and so I need help in building one of them.
We have a file say “GetHistory.bat” and it accepts a parameter ID. The output of the script is as shown below:

Activity Name      Status      Date
----------------------------------------
Act1              Created    1-Jan-2013
Act2              Submitted  2-Jan-2013 
Act3              Approved   2-Jan-2013

Now the problem is I need to export the output in txt as CSV without the header and parameter ID added to each line as below:

1001,Act1,Created,1-Jan-2013
1001,Act2,Submitted,2-Jan-2013 
1001,Act3,Approved,2-Jan-2013

Any help to begin the script would be highly appreciated.
Thanks…!

Answer 1

With the assumption that the output of GetHistory.bat has been redirected into a file called history.txt, we could feed that into our new batch file, ParamCSV.bat, like so, with this result:

C:\stackoverflow>ParamCSV.bat 1001 < history.txt
1001,Act1,Created,1-Jan-2013
1001,Act2,Submitted,2-Jan-2013
1001,Act3,Approved,2-Jan-2013

To put together a quick script for this, I’ve referenced info from:

• Read stdin stream in a batch file
• What is the best way to do a substring in a batch file?
• How to remove trailing and leading whitespace for user-provided input in a batch file?
• DOS Batch – Function Tutorial provided a thorough overview of parameter passing in functions.

I came up with this batch script, ParamCSV.bat:

@echo off
:: ParamCSV.bat
::
:: Usage: ParamCSV.bat <Parameter_ID> < history.txt
::
:: Thanks to:
:: https://stackoverflow.com/questions/6979747/read-stdin-stream-in-a-batch-file/6980605#6980605
:: https://stackoverflow.com/questions/636381/what-is-the-best-way-to-do-a-substring-in-a-batch-file
:: https://stackoverflow.com/questions/3001999/how-to-remove-trailing-and-leading-whitespace-for-user-provided-input-in-a-batch

:: Copy input parameter to 'id'
set id=%1

setlocal DisableDelayedExpansion

for /F "skip=2 tokens=*" %%a in ('findstr /n $') do (
  set "line=%%a"
  setlocal EnableDelayedExpansion
  set "line=!line:*:=!"
  set "activity=!line:~0,17!"
  call:trim !activity! activity
  set "status=!line:~17,11!"
  call:trim !status! status
  set "date=!line:~28,11!"
  call:trim !date! date
  echo(!id!,!activity!,!status!,!date!
  endlocal
)
goto:EOF

::function: trim
::synopsis: Removes leading and trailing whitespace from a sting. Two
::          parameters are expected. The first is the text string that
::          is to be trimmed. The second is the name of a variable in
::          the caller's space that will receive the result of the
::          trim operation.
::
::usage:    call:trim string_to_trim var_to_update
::             e.g.   call:trim %myvar1% myvar2

::trim left whitespace
setlocal
set input=%~1
for /f "tokens=* delims= " %%a in ("%input%") do set input=%%a
::trim right whitespace (up to 100 spaces at the end)
for /l %%a in (1,1,100) do if "!input:~-1!"==" " set input=!input:~0,-1! 
::return trimmed string in place
endlocal&set "%~2=%input%"

There are a number of assumptions that are made here, and if any of them change or are invalid, the script will break:

• The output of GetHistory.bat has fixed-width columns, of width 17,11, and 11. You didn’t provide an example of a two-digit day, so I’ve assumed the dates are right-aligned.
• There are two header lines, which we skip in the for statement.
• All output lines are for the same ID, so only one input parameter is expected, and it is the first element in all CSV output lines.