Question

How Would I find another exe’s path by knowing its name in .net?

Would I add name to the OS environment variable?
Would the other application have to ‘register’ itself somewhere else?

I need App A to start-up App B and call some WCF services on it.

Thanks!

Answer 1

To answer your question: you cannot know the path simply by knowing the name. An exe can reside anywhere on the file system. There can be multiple instances of it that don’t know about each other. Multiple exe files that are completely different can have the same name.

You could take one of several approaches to get round this, depending on the exe you are targetting:

• get the user to browse for the exe using a normal file browse dialog
• search the file system
• see what traces the target exe leaves on the system (filesystem, registry, environmental variables, etc) and use those traces to locate the exe

For either of these options you save the result so you don’t have to execute it again when your app is run the next time.

Searching the filesystem could take some time, you are not guaranteed to find the exe (depending upon the user level your app is running as) and you may get false positives, especially if the app is called something dumb like setup.exe.

Getting the user to locate the exe the first time you run is possibly the most reliable way of locating it, but then you have to decide what to do if your app runs but the target exe is no longer at the specified location, or the user has chosen the wrong exe.

If you have some control over App B (i.e. it is your product), then you could consider adding some info to a known spot in the registry when App B gets installed, so that App A can locate it easily. You still need to have a plan B though in case the info is missing.