DOS – Multi-Line IF Statements in Batch File

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Most folks don't realize it, but you can actually place multiple statements into if-else clauses. In fact, most people don't even realize that the [gs batch] file allows you to have an else clause. The following code demonstrates how you can have multi-line IF statements, so that you don't have to do a lot of goto's.

  if exist %sourceDir% (


    md %targetDir%


    xcopy /E %sourceDir% %targetDir%


    copy %sourceDir%\*.lnk %targetDir%


  ) else (


    echo %SourceDir% not found!


)

The '(' and ')' must be on the same line as the if and else statements as shown above. Even though they are not the open and close bracket, you can think of them as such. With multi-line if-else statements, you batch file can become far more structured than ever.

What doesn’t work and How to fix it

The set variable function does not work inside a multi-statement if-else scope. For example, the following code does not work:

if "%tempDir%" == "" (


    set output=*** Variable tempDir not set!


    echo %output%


    echo %output% >> %logFile%


    set success=false
< )

The [gs batch] [gs processor] was never able to use the %output% that was set within that scope.

SOLUTION 1

The [gs workaround] for this problem is to call a sub-routine in the if statement. The following is an example:

if "%tempDir%" == "" (


    call :subroutine


  )


  goto :end


:subroutine


  set output=*** Variable tempDir not set!


  echo %output%


  echo %output% >> %logFile%


  set success=false


  goto :eof


:end

SOLUTION 2

SetLocal EnableDelayedExpansion


if "" == "" (


  set output=*** hello dude


  echo !output!


)


echo !output!


echo %output%


EndLocal

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