Windows – How to properly escape ‘=’ in the string replacement script

batch filestringwindows

I have made a batch script that replaces strings in a specified text-based file. Within my file, the string OutDir=bin should be replaced as OutDir=Build but gets output as bin=OutDir=Build=bin. How do I escape the = in OutDir=bin so that the string doesn't become garbled? I have tried OutDir^= but using the carrot doesn't work either.

Here is my current script:

@echo off 
    setlocal enableextensions disabledelayedexpansion

    set search=OutDir=bin
    set replace=OutDir=Build

    set textFile=%DOCUMENT%.txt

    for /f "delims=" %%i in ('type "%textFile%" ^& break ^> "%textFile%" ') do (
        set "line=%%i"
        setlocal enabledelayedexpansion
        >>"%textFile%" echo(!line:%search%=%replace%!
        endlocal
    )

I have attempted to change the find and replace variables to compensate for the = in the string I'm replacing but none have worked:

set search= "OutDir=bin"
set replace= "OutDir=Build"

set search="OutDir=bin"
set replace="OutDir=Build"

set "search=OutDir=bin"
set "replace=OutDir=Build"

"set search=OutDir=bin"
"set replace=OutDir=Build"

Best Answer

Replacing the Equal Symbol `=` in a String with Batch using PowerShell

After testing and then research afterwards, I came upon this answer on StackOverflow which then also pointed to this thread and posts on DosTips and replacing the = with pure batch isn't easy.

When I run into issues with batch scripting where it takes a ton of complex batch logic or just cannot figure out how to get it to work easily, I usually try incorporating some PowerShell into the mix since it's Windows native and it can be much more robust than batch without complex logic.

The below batch script will essentially:

Use Get-Content and Replace for the string to search and replace

Then it will use Set-Content to put the newly replaced string back into the file accordingly

Script

@echo off
setlocal enableextensions disabledelayedexpansion

set search=OutDir=bin
set replace=OutDir=Build
set textFile=%DOCUMENT%.txt

:PowerShell
SET PSScript=%temp%\~tmpStrRplc.ps1
ECHO (Get-Content "%~dp0%textFile%").replace("%search%", "%replace%") ^| Set-Content "%~dp0%textFile%">"%PSScript%"

SET PowerShellDir=C:\Windows\System32\WindowsPowerShell\v1.0
CD /D "%PowerShellDir%"
Powershell -ExecutionPolicy Bypass -Command "& '%PSScript%'"
EXIT

Output Result

OutDir=Build

Further Resources

Related Solutions

Run this bat file with admin rights

Native runas cannot be passed a password, you'd have to use a 3rd party app. The following is free, the full version allows you to encrypt the password:

http://www.softtreetech.com/24x7/archive/53.htm

Then you could call the batchfile from within another batchfile containing the following:

runas user@domain.com password yourbatchfile.bat

That's about the best solution I can come up with for you ...

Windows – String replacement in Windows batch

You have a couple problems:

%var% expansion occurs when the statement is parsed, and the entire parenthesized code block is parsed in one pass, before any commands are executed. So the value is the value that existed before the loop was started. The solution is delayed expansion, which occurs as each command within the loop is being executed.
Your logic is wrong - the assignment of _newp should be based on the value of _srcp

The CMD processor is a complicated beast (and also poorly documented). There are multiple points where various types of variables are expanded, and you must fully understand them if you truly want to make the most of batch programming. It is all explained in the link, but in summary, the order of expansion is:

1) % expansion - Parameter: echo %1 or Environment variable: echo %var%
---- Most parsing has completed by now ----
2) FOR variable expansion: for %%A in (*) do echo %%A
3) Delayed environment variable expansion: echo !var!
4) CALL % expansion - Parameter: call echo %%1 or Environment variable: call echo %%var%%
5) SET /A environment variable expansion: `set /a "value=var+1"

Note that delayed expansion requires delayed expansion to be enabled via SETLOCAL EnableDelayedExpansion

The following code using delayed expansion will give the result you seek:

@echo off
for /D %%G in (*) do (
  setlocal enableDelayedExpansion
  echo G is: %%G
  set "_srcp=%%G"
  echo _srcp is !_srcp!
  set "_newp=!_srcp:ai=_01_!"
  echo _newp is: !_newp!
  endlocal
)

Note that delayed expansion occurs after FOR variable expansion, so the result will be corrupted if %%G constains !. This can be avoided by additional SETLOCAL:

for /D %%G in (*) do (
  setlocal disableDelayedExpansion
  echo G is: %%G
  set "_srcp=%%G"
  setlocal enableDelayedExpansion
  echo _srcp is !_srcp!
  set "_newp=!_srcp:ai=_01_!"
  echo _newp is: !_newp!
  endlocal
  endlocal
)

You could also get the desired result using CALL with double percents, but this is much slower. The speed is not important if executed a few times, but it becomes very significant if executed thousands of times in a loop.

@echo off
for /D %%G in (*) do (
  setlocal
  echo G is: %%G
  set "_srcp=%%G"
  call echo _srcp is %%_srcp%%
  call set "_newp=%%_srcp:ai=_01_%%"
  call echo _newp is: %%_newp%%
  endlocal
)