Couple of ?s about VB and NSIS

Hi,

1. I went through the FAQ and the archives, and found exemples on how to build a small, through-the-web installer to fetch the VB runtime from the web:

ExecShell "open" "http://www.whatever.com/downloadthis.exe"

=> How reliable is this? As I'm just starting with NSIS, does someone have a full script to install the VB runtime trough the web?

2. I'd like to write a routine in Sub Main() that will
- query a web app for all the dependencies for a given app (eg. www.acme.com/list.php?app=myapp -> get CSV-formatted list)
- for each and every dependendy, check that it's already installed
- if not, fetch it from the web

=> Can I use nsisdl.dll to perform this task from a VB app? Does someone have an example?

Thank you, and a happy new year
JD.

Hello there:

1. It's reliable. 😁
You'll have to use NSISdl for that... The Nsis Web archive has cool examples.

2. NSIS' Function .onInit is like VB's Form_Load() or Sub Main(). But NSIS is nothing like VB; although both are programming languages and have the same logic.

I wouldn't rely on ExecShell. You can't wait for it like you can with ExecWait and nothing assures you the user hasn't set http:// handling to a browser that will allow the user to open the file. For example, Mozilla browsers just offer to save EXE somewhere for security reasons, at least the last time I use Mozilla.

As for the CSV file, I think an INI file would be simpler to manage. Instead of opening and parsing the file you'll only need to call ReadINIStr.

>>NSIS' Function .onInit is like VB's Form_Load() or Sub Main()

Thanks but... can I use nsisdl.dll from VB to automate the whole dependency check + download part instead of reinventing the wheel? Anybody has the DECLARE required to call it from VB?

Thank you
JD.

I don't think it'd be easy to use NSISdl in VB. It would probably be easy to call a NSIS installer which will call NSISdl or just download using VB.

You can also check the dependencies using NSIS. See the users manual for information about commands to check DLL versions.

Interesting... I hadn't thought about building an installer that could be called either explicitely for the initial install, or silently every time my app starts to delegate the checking + downloading of missing components or updates.

I'll see what I can do. Thanks :-)
JD.