"Auto Updatable" application
Posted on 2004-04-15
here is a theoric question, I want to investigate the different possibilities before starting.
I have an application that will be deployed at several places in several cities. When a new version of the application is released, I do not want to go to each place and redeploy the new version, and I do not want the users to do that themselves.
So I had several ideas.
At every startup of my application, it could check if a new version is available (comparing its version with a value returned by a web service for instance). If it is the case, uninstall itself and install it again. (maybe using an external process and working in command line... is it doable ? Can we install a .NET application without using the msi wizard ? What happens if the user doesn't have local administrator rights ? can we install for everyone ?
Quite similar, but it will update only a DLL. My application will be a small exe, doing for instance just a myDllEntryPoint.Start() or something like that.
Of my course, my new DLL will have a higher version number and so I believe there will be a problem for my soft. It won't use the new DLL as the version number is no longer correct. How can we change that ?
Using a distant DLL. Like in previous case, my application would launch only a start method in the DLL, but this DLL would be installed in the GAC of a distant computer. So when a new version is released, I only uninstall and reinstall that DLL on the server.
Can we use a distant DLL ? (and how ?) Only on a local network ? Also thru a VPN ? Is there a drawback in term of performance (I was thinking that the DLL would be loaded at every startup in memory... Is that true ? Will it have to go to the server each time a methof of the DLL is called ?)
Do you have another / better idea ?
What would you do in such a case ?