Visual Studio 2008 - Build Event: How to use Variable (set tmp="abc" and %abc%)?

batch-file, environment-variables, post-build-event, set, visual-studio-2008

Solution

You have a classic problem for batch newbies - You can't look at a value you just set within a loop (parentheses) because the entire loop is parsed at once. So you are seeing the value of your variable before the loop was executed - obviously not going to work. The solution is to enable delayed expansion with `SETLOCAL EnableDelayedExpansion` and then expand your variable using delayed expansion as `!var!`.

Your other issue of how to get the file attributes - you can use the `~a` FOR variable expansion modifier to get the list of attributes. In typical Microsoft fashion, the attributes are not listed in the same order or case as the ATTRIBUTES command. The read only flag is `r` in the 2nd character (position 1).

Both delayed expansion and modifiers are explained in the documentation: Simply type `HELP FOR` or `FOR /?` from a Windows command line. Simply run `CMD` from the Start menu to get a command line.

setlocal enableDelayedExpansion
if $(PlatformName)==x86 (
  echo x86
  for %%F In ("Attrib $(ProjectDir)..\..\somedir\$(ConfigurationName)\somemoredir\$(TargetName).dll") do set _Attribs=%%~aF
  if not "!_Attribs:~1,1!"=="r" (
    set test="monkey"
    echo !test!
    echo $(test)
    echo nono
    echo !_Attribs!
    echo $(ProjectDir)..\..\somedir\$(ConfigurationName)\somemoredir\$(TargetName).dll
    attrib $(ProjectDir)..\..\somedir\$(ConfigurationName)\somemoredir\$(TargetName).dll
    xcopy /Y $(ProjectDir)..\..\..\Runtime\bin\$(TargetName).*  $(ProjectDir)..\..\somedir\$(ConfigurationName)\somemoredir\
  )
)

You could use the ATTRIB command as in your original command - just make sure to use `!_Attribs:~5,1!` instead of `%_Attribs:~5,1%`. But the `~a` modifier solution I provided is more efficient since it uses a simple FOR loop and doesn't have to execute a command using FOR /F.

Problem

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