Bat file to replace a specific String

Question

I am looking for a Bat Files that changes a line in a file. Let me give you an example to make it clear. I have a file test.properties

The file looks like this:

hostname=<hostname>
port=0
rpcqueue=0
defaultlocale=en
defaulttimeout.normal=0
defaulttimeout.long=0
defaulttimeout.xlong=0
name=admin
passwd=406abbc8192eda42cc3261235959e23a8e223f6ab7f10d8cdf2e22fca

So I want to replace the value behind passwd but my problem is I don't know this value I only know the value with which i want to replace the old one.

It should also be possible to enter the file name, the attribute value (passwd) and the new value over command line so that I could use this file for other files to. Sorry if this question is already somewhere but I couldn't find it.

My knowledge about bat is not superior and I am learning.

Thanks!

Answer 1

Launch this batch file like this: Mybatch newpassword

This uses a helper batch file called repl.bat - download from: https://www.dropbox.com/s/qidqwztmetbvklt/repl.bat

Place repl.bat in the same folder as the batch file or in a folder that is on the path.

@echo off
type "test.properties" |repl "(passwd=).*" "$1%1" >"newfile.properties"

Answer 2

Use the script below in command line as folowing: script.bat eg> script.bat test.txt passwd someval script will parse your file looking for "varName=", if it finds it, it replaces value with newVarValue. All output is redrected to a temp file and after that temp file replaces initial one.

@echo off
set "filepath=%~1"
set "pname=%~2"
set "value=%~3"

(
    for /F "tokens=*" %%a in ('type "%filepath%"') do (
        echo "%%a" | findstr /C:"%pname%=" > nul 2>nul
        if "!errorlevel!"=="0" (
            echo %pname%=%value%
        ) else (
            echo %%a
        )
    )
)>"%filepath%.tmp"

move /Y "%filepath%.tmp" "%filepath%"