installing system component if not existing before install

[Bernard Laurent]

Hello,

I would like to install Microsoft Access Runtime, before installing my application, if it's not already installed.

I saw that I can use a beforeinstall parameter in [Files] section, but I don't know how to do that, as if have not for example to manage DestDir: ...

Should these below lines be correct ?

[Files] Source: "MicrosoftAccessRuntime.exe"; BeforeInstall: MyBeforeInstall

[Code] procedure MyBeforeInstall(); begin MsgBox('About to install Microsoft Access Runtime as ' + CurrentFileName + '.', mbInformation, MB_OK); end; 

Thanks for your help !

Bernard

[Gavin Lambert]

On Thursday, August 22, 2024 at 9:25:17 PM UTC+12 Bernard Laurent wrote:

I would like to install Microsoft Access Runtime, before installing my application, if it's not already installed.

I saw that I can use a beforeinstall parameter in [Files] section, but I don't know how to do that, as if have not for example to manage DestDir: ...

No, that's not the right way to do that sort of thing.

You can install the [Files] to {tmp} and then use an AfterInstall to actually Exec the installer, but this is not recommended practice either.

The recommended way to handle installation of prerequisites is to write [Code] in PrepareToInstall.  See the CodePrepareToInstall example included with Inno for some of the basic structure -- the extra piece is that for the actual installation you will need to use ExtractTemporaryFile and Exec (and interpret exit codes appropriately).  If this is the only use of the file, you can also mark it with Flags: dontcopy.

[Andrew Truckle]

See Inno Dependency Installer:

https://github.com/DomGries/InnoDependencyInstaller

It is simple to use, and works very well.