Variable doesn't get updated in the function of Batch file

Question

I have a simple batch script that will read the value in file version.property and perform a certain job my code is below

TITLE StartEODMaintenance
echo o         


        

Answer 1

The big problem is that your script continues to :FindString as part of the main runtime. On line 6 you call :FindString "MAINALGO", then you've got an IF code block. After that code block, you should exit /b or goto :EOF or something to halt execution of the main runtime, but you don't. Instead, your script continues to :FindString a second unintended time, sets %ERRORLEVEL% by find /I /C "" version.property, and continues to the end.

Something else you might find interesting is conditional execution. Instead of

find /I /C "%~1" version.property
if %errorlevel%==1 (
echo "errorlevel 1"
set "Build=0"
)
if %errorlevel%==0 (
echo "errorlevel 0" 
set "Build=%~1"
echo build value in function %Build%
)

... or ...

find /I "%~1" version.property
if errorlevel 1 (
    echo "errorlevel 1"
    set "Build=0"
) else (
    echo "errorlevel 0" 
    set "Build=%~1"
    echo build value in function %Build%
)

... you could condense your code a bit like this:

find /I "%~1" version.property && (
    echo "errorlevel 0" 
    set "Build=%~1"
    echo build value in function %Build%
) || (
    echo "errorlevel 1"
    set "Build=0"
)

I also recommend that you avoid being lazy with your indenting and formatting. While your code isn't nearly as bad as it could be, it would still be a little easier to see what's going on in :FindString if you indent your code blocks.

Anyway, see whether you have better luck with this:

TITLE StartEODMaintenance
echo off
cls
set "Build=0"

call :FindString "MAINALGO"

IF /I "%Build%"=="MAINALGO" (
    echo "start job on MainAlgo"
) else (
    call :FindString "DRSITEALGO"
    echo build value %Build%
    IF /I "%Build%"=="DRSITEALGO" (
        echo "start job on secondAlgo"
    ) else (
        echo "sth wrong"
        rem // exit non-zero
        exit /b 1
    )
)

exit /b 0
rem // end main runtime / begin script functions

:FindString
find /I "%~1" version.property && (
    echo "errorlevel 0" 
    set "Build=%~1"
    echo build value in function %~1
) || (
    echo "errorlevel 1"
    set "Build=0"
)

Answer 2

The %variables% are expanded when the command is parsed and the command if followed by a block is parsed at once. So when you set a variable in the block, its following usage (in echo here) has been expanded already and it results in showing the value that was valid before entering the block!

You need delayed expansion to read variable values at the moment when they are used, not parsed. First, issue the command:

setlocal EnableDelayedExpansion

Then refer to the variables modified earlier within the same block as !variable!.

if %errorlevel%==0 (
echo "errorlevel 0" 
set "Build=%~1"
echo build value in function !Build!
)