Setting a variable at run time

Question

I am making an NSIS script which checks if a previous version of the application is installed. If so, it asks whether or not the configuration file should be imported from this previous version. So I have a global variable config file which I am trying to set at runtime depending on whether the user chooses "yes" or "no". The problem I am having is when compiling it complains with File: "${XMLConfigDir}*.xml" -> no files found. because XMLConfigDir has not been set yet. So is there anyway to set a variable at runtime?

score 11 · Answer 1 · answered Aug 15 '12 at 16:51

11

There is difference between declaring variables (Var command) and symbols (defined with !define command):

Var /GLOBAL myVar ; This is variable -> use it as $myVar

!define mySymbol; This is symbol -> use it as ${mySymbol}

Try this:

!define XMLConfigDir "C:\some_path_to_XML\subdir\"

Section "Main Section" 
        File "${XMLConfigDir}*.xml"
SectionEnd

Symbols can be also set using /D command line switch during installer runtime.

answered Aug 15 '12 at 16:51

Slappy

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/D switch can be also used during compilation as: makensis.exe /DmySymbol="C:\some_path_to_XML\subdir\" script_to_compile.nsi – Slappy Aug 15 '12 at 18:02
1

Cheers for the info but I don't understand how it answers my question of not being able to use the File command with a variable which is unknown at compile time but determined at runtime. – Harry Aug 16 '12 at 09:48

score 2 · Accepted Answer · answered Aug 17 '12 at 12:25

2

The solution to my problem was to use the CopyFiles built in function rather than the SetOutPath followed by File.

answered Aug 17 '12 at 12:25

Harry

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Setting a variable at run time

2 Answers2