Check section by rule

[PepaR]

Could you give someone exaple how check section if I find some string in registry?
Eg. I have a lot of version program for which is make this setup. I recognize in registry that progam is install, but how automatic activate checbox with relevant section of files?

Thanks for reply

[Red Wine]

code:
Name "My Application"

OutFile 'test.exe'

LicenseData '${NSISDIR}\License.txt'

InstallDir '$PROGRAMFILES\$(^name)'

ShowInstDetails show



Page License

Page Components comp_pre

Page Directory

Page InstFiles



Section "!Required Section" sec1

SetOutPath "$INSTDIR"

detailprint "Required Section: Always installed"

SectionEnd



section /o "Install NSIS Plugin" sec2

Setoutpath "$0"

detailprint "Section: Install NSIS Plugin"

sectionend



section /o "Install Dummy Plugin" sec3

Setoutpath "$1"

detailprint "Section: Install Dummy Plugin"

sectionend



function comp_pre

ReadRegStr $0 HKLM "Software\NSIS" ""

Iferrors 0 +3

sectionsettext ${sec2} ""

goto +2

sectionsetflags ${sec2} 1

clearerrors

ReadRegStr $1 HKLM "Software\Dummy" ""

Iferrors 0 +3

sectionsettext ${sec3} ""

goto +2

sectionsetflags ${sec3} 1

functionend